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Tobacco smoking is a well-known risk factor for both fibrogenesis and fibrotic progression; however, the mechanisms behind these processes remain enigmatic. RTKs (receptor tyrosine kinases) have recently been reported to drive profibrotic phenotypes in fibroblasts during pulmonary fibrosis (PF). Using a phospho-RTK array screen, we identified the RTK AXL as a top upregulated RTK in response to smoke. Both expression and signaling activity of AXL were indeed elevated in lung fibroblasts exposed to tobacco smoke, whereas no significant change to the levels of a canonical AXL ligand, Gas6 (growth arrest–specific 6), was seen upon smoke treatment. Notably, we found that smoke-exposed human lung fibroblasts exhibited highly proliferative and invasive activities and were capable of inducing fibrotic lung lesions in mice. Conversely, genetic suppression of AXL in smoke-exposed fibroblasts cells led to suppression of AXL downstream pathways and aggressive phenotypes. We further demonstrated that AXL interacted with MARCKS (myristoylated alanine-rich C kinase substrate) and cooperated with MARCKS in regulating downstream signaling activity and fibroblast invasiveness. Pharmacological inhibition of AXL with AXL-specific inhibitor R428 showed selectivity for smoke-exposed fibroblasts. In all, our data suggest that AXL is a potential marker for smoke-associated PF and that targeting of the AXL pathway is a potential therapeutic strategy in treating tobacco smoking–related PF.

Continuous scaling of device dimension pushed Si channel to its physical limit, alternative high mobility channels such as (Si)Ge and (In)GaAs have been considered to replace Si to further enhance CMOS performance. In the meantime, ultrathin body (UTB) semiconductor-on-insulator is compulsory structure for improved gate control and immunity against short channel effects in the ultimately scaled high performance and low power dissipation CMOS. To realize stacked multi- channel semiconductor-on-insulator platform on current mainstream Si wafers, layer transfer technology [1-3] utilizing direct bonding and selective etching was developed to integrate (Si)Ge or (In)GaAs channels on Si, showing great potential for ultimate device structures with heterogeneous integration. Figure 1(a) is the process flow for integrating InGaAs channel onto SiGe-on-insulator (SGOI) structure utilizing layer transfer technology [4]. It started with bottom SGOI pMOSFET fabrication. The SGOI structure was realized by 2-step Ge condensation technique, resulting in Ge content of 70%. After high k metal gate process, self-aligned Ni-SiGe alloy was formed as S/D metal. Subsequently, SiO2 interlayer was deposited by CVD, followed by CMP planarization. Then, InGaAs grown on InP was directly bonded onto SiO2 and InP substrates were selectively etched away. Finally, the top InGaAsOI nMOSFET fabrication and metal interconnection completed the CMOS fabrication. Fig. 1(b) shows the cross-sectional TEM images of fabricated InGaAs/SiGe channel stacked CMOS. Well aligned top and bottom devices are seen without any distinct defects. Figures 2 is a schematic flow for fabricating Ge/Si double channel-on-insulator structure by low temperature hetero-layer bonding technology (LT-HBT). The technology starts with the preparation of donor wafers (Fig. 2(a)) for the top Ge channel layer and host wafers (Fig. 2(b)) for the bottom Si channel layer. For donor wafers, a 200-nm-thick Ge was epitaxially grown on SOI wafer by reduced pressure CVD. After CMP planarization, ALD SiO2 is deposited onto Ge. For host wafers, implantation and dopant activation were carried out, followed by chemical treatment for Si oxidation. After surface activation by room temperature chemical treatment (Fig. 2(c)), the direct wafer bonding of both SiO2 surface was performed at 200 °C in a press machine (Fig. 2(d)). Then, the Si substrate of the donor wafer was removed with deep RIE. At this time, the BOX layer of the donor wafer serves as an etch-stop layer. Subsequently, the BOX layer and thin Si layer of the donor wafer were removed selectively in HF and TMAH solution, respectively (Fig. 2(f)). To precise control the top Ge channel thickness, a series of low damage etching process was adapted to thin down Ge (Fig. 2(g)). The realized double channel structure is fully isolated with an insulating insertion layer,[5] which is very promising for realizing novel complementary FET (CFET) with minimum process steps. The cross-sectional TEM image of Ge/Si stacked channel of CFET after high k metal gate process is demonstrated in Fig. 2(h). Even more multiple stacks can be realized by using LT-HBT. A vertically stacked three-layer structure with 2 bottom Si layers and 1 top Ge layers is also demonstrated using SOI-based donor wafers in Fig. 3, indicating the highly integrated density channel structure is possible. The feasibility of layer transfer technology has been proved for multi-channel structure with high mobility channels for N2 node and beyond. Acknowledgement This work was supported by JST Japan-Taiwan Collaborative Research Program, Grant Number JPMJKB1902, Japan and the Ministry of Science and Technology under Grant Number MOST-109-2628-E-492-001-MY3, 109-2923-E-492-001-MY3, 107-2221-E-492-016-MY3. References [1] T. Maeda et al., Appl. Phys. Lett. 109, 262104 (2016). [2] W. H. Chang et al., Mater. Sci. Semicond. Process 70, 123 (2017). [3]W. H. Chang et al., IEEE Trans. Electron Device 64, 4615 (2017). [4] T. Irisawa et al., VLSI 146 (2014). [5] T. Z. Hong et al., IEDM (2020) Figure 1

Monolithic 3D (M3D) integration has been thought of as an attractive idea to realize multi-functional heterogeneous integration devices. M3D integration enables us to combine logic devices with different functional devices such as memory, sensor, or optics to create extremely compact and efficient system-on-chips. Ge and III-V compound semiconductors are expected to be implemented as high mobility channel materials and optical components which cannot be realized with Si. The layer transfer technique with low processing temperature has great potential for stacking non-lattice-matched crystalline materials for M3D ICs. Here, we discuss the layer transfer technology utilizing high quality epitaxial growth, low-temperature direct bonding and advanced epitaxial lift-off (ELO) process, which reveals the applicability of transferred layers for heterogeneous integration. The low temperature ELO process is essential for realizing reliable layer transfer with different materials because the process is almost free from the issues of thermal expansion mismatch. Process flow of GaAs or Ge layer transfer with ELO process is described in Fig. 1. First of all, a lattice-matched single crystal GaAs or Ge layer is epitaxially grown on GaAs substrate with an AlAs release layer by MOCVD. Subsequently, Al2O3 layer is deposited on the epitaxial layer by atomic layer deposition (ALD). ALD Al2O3 layer serves as the buried oxide (BOX) and the passivation layer for Ge or GaAs surface. Then, Ge or GaAs layer is patterned using photolithography. The patterned GaAs or Ge/AlAs/GaAs donor wafer is then bonded on host substrate by direct bonding technique with wet activation process. Finally, the epitaxial GaAs or Ge layer is transferred on host substrates by splitting GaAs donor wafer from AlAs layer with HCl side etching thanks to extremely high etching selectivity. Note that the fabrication of patterned transfer layer is effective in shortening the required time of ELO process. In this ELO process, the thickness of a transferred layer can be control by epitaxial layer thickness. After the layer transfer process, the released donor GaAs wafer can be reclaimed and reused for the subsequent re-epitaxial growth to reduce the process cost. Figs. 2 (a) and (b) show cross-sectional SEM and TEM images of fabricated GeOI substrate with different BOX structures. Ge pattern edge shows no peeling from SiO2(100nm)/Si substrate, indicating strong bonding strength at the pattern edge. In Fig. 2 (b), the bonding interface is clearly observed at Al2O3(5nm)/SiO2(50nm) interface formed by the wet activation process. The bonding interface exhibits very smooth and no defect. There is no observable defect in transferred Ge layer, suggesting dislocation density is below TEM detection limit. Compared to Smart-CutTM technique, ELO process has significant advantages in terms of crystal quality, thickness control and the surface flatness thanks to totally low temperature processing. To reduce wafer-scale thickness variation, etching stopper (ES) technique with high etching selectivity is quite useful. As a donor wafer, we prepare Ge active layer (20nm)/SiGe ES layer (5nm)/Ge buffer layer/AlAs/GaAs structures. Here, the SiGe layer serves as ES against the etching of Ge buffer layer to control the final GeOI thickness and attain the wafer-scale thickness uniformity. In addition, Si passivation on Ge surface was performed during initial epitaxial growth of donor wafer since Si passivation was proved to be effective in reducing interfacial trap density (D it) between Ge and oxide. After ELO process, Ge buffer layer /SiGe ES layer/Ge active layer / Al2O3 /SiO2/Si heterostructure was obtained. Then, the top Ge buffer layer was removed in HCl/H2O2 solution. We found the etching selectivity was more than 30 between Ge and SiGe layer, which is high enough to yield very smooth SiGe surface. Finally, SiGe layer was removed by TMAH preferentially. Further conformal thinning of Ge active layer was performed by the cyclic dry oxidation/wet digital etching (DE) at room temperature. In addition to thickness control with the etching rate of about 0.8 nm/cycle, it is found that dozens digital etching (DDE) process is effective for reducing Ge surface roughness. Finally, UTB GeOI substrates with high crystal quality down to 3 nm have been successfully fabricated through SiGe ES and DDE processes. Ultra-smooth GeOI surface with reduced thickness fluctuation was confirmed after DDE by TEM cross-sectional images, resulting in significant improvement of device performances. Figure 1

Advanced channel formation technologies called HEtero-layer-lift-off utilizing SiGe heteroepitaxy have been realized for fabricating ultrathin body (UTB) Ge-on-insulator (GeOI) structures. Insertion of SiGe etching stop layer was found to be effective for reducing GeOI body thickness ( $T_{\mathrm {body}}$ ) fluctuation. Backside Si passivation for Ge/buried oxide interface has been verified to suppress backside Coulomb scattering and help to induce volume inversion effect. With improvement of backside interfacial quality and precise control of GeOI $T_{\mathrm {body}}$ , primary carrier scattering factors in GeOI channel have been effectively reduced, resulting in significant improvement of hole mobility. High hole mobility of ~150 cm2/Vs in UTB GeOI pMOSFETs without strain technology has been demonstrated, which also outperformed Si universal mobility by 1.5 times even under $T_{\mathrm {body}}$ of 9 nm. With low-thermal-budget process compatibility, UTB GeOI platform is very promising for future Ge large-scale integrated circuits devices used in monolithic 3-D integration scheme.

Nanoelectronics require semiconductor nanomaterials with high electron mobility like Ge nanolayers. Phonon and electron states in nanolayers undergo size-dependent changes induced by confinement and surface effects. Confined electrons and acoustic phonons determine layer optical, electric and thermal properties. Despite scientific and practical significance, their experimental studies in individual nanolayers are still lacking. Thanks to recent progress in the fabrication of high-quality nanolayers, here, we report the thickness dependencies of Raman spectra of acoustic phonons and optical spectra of electrons confined in germanium-on-insulator (GeOI) nanolayers with thicknesses TGeOI = 1–20 nm. We show that for TGeOI > 5 nm, both GeOI acoustic phonon Raman spectra and the E1 electron energy gap display dependencies on TGeOI which are reasonably described by the corresponding phonon and electron confinement theories. Accordingly, TGeOI can be probed using acoustic phonon Raman spectra at TGeOI > 5 nm. However, both confinement theories fail to describe GeOI thickness dependencies at TGeOI < 5 nm. We attribute this discrepancy to an increased influence of the Ge–GeO2 interface disorder with TGeOI reduction. The acoustic phonon data suggest a decrease of Ge normal-to-the-layer longitudinal sound velocity. Generation of interface-disorder-induced dispersionless phonons might contribute to this. The change in GeOI phonon properties at TGeOI < 5 nm might influence E1(TGeOI) dependence via a change in the GeOI electron–phonon interaction. We demonstrate that the Al2O3 coating improves the agreement between experimental and confinement theories, probably, via reduction of disorder at the Ge–GeOx–Al2O3-interface. Our results are important for control of nanolayer-confined electrons and phonons with benefits for modern and future nanoelectronic devices.

The electromagnetic wave of 1.0 terahertz (THz) was detected using a square law detector made of InAs quantum-well (QW) metal-oxide-semiconductor field effect transistors (MOSFETs) fabricated on quartz. The voltage responsivity of 1.7 kV/W was achieved at room temperature. The noise equivalent power (NEP) was evaluated to be below $\mathbf{2\ pW}/\mathbf{Hz}^{\mathbf{0.5}}$ . A new circuit model which well explains the detection characteristic and dependence of the sensitivity on physical parameters of MOSFETs is proposed. These results prove the high potential of InAs QW MOSFETs on quartz for implementation of THz imaging.

The impact of channel flattening process, dozen digital etching (DDE), on device performance and reliability of Ge nMOSFETs with different surfaces of (100), (110) and (111) has been systematically investigated. It was found, for the first time, that DDE improves not only electron mobility but also gate oxide reliability, especially on Ge (100). Decrease of surface roughness, as well as interfacial/bulk trap densities in gate oxide could explain these phenomena. Thanks to DDE, the electron mobility of Ge (100) devices can compete with those of Ge (111) devices while possessing higher reliability.

By using a transparent conductive oxide (TCO) gate for the short-wave infrared (SWIR) region, the high optical responsivity of 180 A/W at 1550 nm and the broadband photosensitivity up to 1800 nm are demonstrated in InGaAs photo field-effect transistors (photoFETs) with front-side illumination (FSI). The photoresponse of the InGaAs photoFETs through the TCO gate can be reasonably explained by the photovoltaic effect in the photoFET operation. It was found that the spectral responsivity characteristics of TCO gate InGaAs photoFETs exhibit higher and broader responsivity compared with those of the InGaAs photodiode. The TCO gate InGaAs photoFETs are the most promising architecture for a high responsivity and broadband SWIR FSI photodetector for monolithic integration with optical communication devices and Si-LSI.

Position and growth direction control in chemical vapor deposition (CVD) of WS2 and SnS2 by using patterned Si/SiO2 substrates has been demonstrated. It was found that step edges effectively worked as crystal nuclei and lateral crystal growth from the edges with a certain level of growth directionality was observed. Gas source CVD using industrially friendly precursors (WF6 SnCl4, and H2S) has also been developed and WS2 and SnS2 synthesis with wafer-scale uniformity have been obtained.

In this study, a new type of field-effect transistor (FET)-based biosensor is demonstrated to be able to overcome the problem of severe charge-screening effect caused by high ionic strength in solution and detect proteins in physiological environment. Antibody or aptamer-immobilized AlGaN/GaN high electron mobility transistors (HEMTs) are used to directly detect proteins, including HIV-1 RT, CEA, NT-proBNP and CRP, in 1X PBS (with 1%BSA) or human sera. The samples do not need any dilution or washing process to reduce the ionic strength. The sensor shows high sensitivity and the detection takes only 5 minutes. The designs of the sensor, the methodology of the measurement, and the working mechanism of the sensor are discussed and investigated. A theoretical model is proposed based on the finding of the experiments. This sensor is promising for point-of-care, home healthcare, and mobile diagnostic device.

We perform Technology computer-aided (TCAD) simulations for 2D material based Junctionless FET (JLFET) and investigate the effect of the fringe-field interaction between the source/drain (S/D) electrodes and the 2D channel. We find that subthreshold slope (SS) gets worse by the fringe-field interaction, and the degradation of the SS becomes serious when the work function difference becomes large. Interestingly, we also find that high drain voltage recovers the degradation of the SS.

We demonstrated high-quality single crystal Germanium (Ge) layer transferred on arbitrary substrates, such as Si, glass, and flexible plastic substrates utilizing direct bonding and epitaxial lift-off (ELO) techniques. Owing to Ge epitaxial growth on GaAs substrates with AlAs release layer, we successfully transferred epitaxial Ge layers on arbitrary substrates with a wide range of thickness from several um to $\sim 1$ nm. This layer tranfer approach enables us to realize Ge-based monolithic 3D devices without degradation of Ge crystalline quality.

High-k dielectrics of Al 2 O 3 , HfO 2 and ZrO 2 have been directly deposited on MoS 2 through plasma enhanced atomic layer deposition (PEALD). Among them, PEALD-ZrO 2 /MoS 2 has shown the highest interfacial quality with high dielectric constant and sharp interface, characterized by CV, XPS and TEM measurements. Dual gate CVD-grown MoS 2 MOSFETs using PEALD-ZrO 2 as a top-gate dielectric has also been demonstrated.

Backside Si passivation for ultrathin boy (UTB) GeOI has been verified to suppress Coulomb scattering from Ge/buried oxide (BOX) interface. With improvement of backside interfacial quality, primary carrier scattering factors in GeOI channel have been effectively reduced, resulting in significant enhancement of hole mobility. The hole mobility improvement has been proved through device characterizations of UTB GeOI $p$ MOSFETs and Hall measurements. UTB GeOI platform formed by only low thermal budget processes is very promising for future Ge large scale integrated (LSI) circuits devices in monolithic 3D (M3D) integration scheme.

X-inactive-specific transcript (XIST), a long non-coding RNA, is essential for the initiation of X-chromosome inactivation. However, little is known about other roles of XIST in the physiological process in eukaryotic cells. In this study, the bioinformatics approaches revealed XIST could be processed into a small non-coding RNA XPi2. The XPi2 RNA was confirmed by a northern blot assay; its expression was gender-independent, suggesting the role of XPi2 was beyond X-chromosome inactivation. The pull-down assay combined with LC-MS-MS identified two XPi2-associated proteins, nucleolin and hnRNP A1, connected to the formation of G-quadruplex. Moreover, the microarray data showed the knockdown of XPi2 down-regulated the KRAS pathway. Consistently, we tested the expression of ten genes, including KRAS, which was correlated with a G-quadruplex formation and found the knockdown of XPi2 caused a dramatic decrease in the transcription level of KRAS among the ten genes. The results of CD/NMR assay also supported the interaction of XPi2 and the polypurine-polypyrimidine element of KRAS. Accordingly, XPi2 may stimulate the KRAS expression by attenuating G-quadruplex formation. Our present work sheds light on the novel role of small RNA XPi2 in modulating the G-quadruplex formation which may play some essential roles in the KRAS- associated carcinogenesis.

The fabrication of high-performance Ge nMOSFET and pMOSFET by using the ion implantation after germanidation (IAG) technique is demonstrated. TaN/Al2O3/GeO2 is deposited as a common gate stack for the low-temperature gate-first process. Both Ge nMOSFET and pMOSFET exhibited a high $I_{\mathrm{\scriptscriptstyle ON}}/I_{\mathrm{\scriptscriptstyle OFF}}$ ratio of $> 10^{4}$ ( $I_{s})$ , a reasonable subthreshold swing of approximately 100 mV/decade, and a low parasitic resistance $ - $\mu \text{m}$ . The IAG technique is proved to be a low thermal budget technique for fabricating both Ge nMOSFET and pMOSFET below 400 °C.

To enhance the feasibility of 2-dimensional transition metal dichalcogenides (TMDCs) channels in future nano-electronic and optoelectronic devices, a top gate device structure fabricated with very-large-scale-integration compatible process is mandatory. High-κ dielectric ZrO2 has been directly deposited on MoS2 through low-temperature atomic layer deposition (ALD) without any surface protection layers. The uniform growth of ZrO2 on MoS2 was confirmed to be caused by the physical adsorption, resulting in the suppressed interfacial oxidation and the reduced damage of monolayer (1L) MoS2 channel. Low thermal budget post-deposition annealing was found to be effective for reducing interfacial traps between ZrO2 and MoS2 interface, thus enhancing the device performances of 1L MoS2 nMOSFETs. Low capacitance equivalent thickness (CET) of ZrO2 of 2.3 nm has been achieved while maintaining decent device performance, indicating low-temperature ALD is promising for future TMDC top gate devices with a high-quality interface and thin CET.

Amorphous Al2O3 films deposited by atomic layer deposition (ALD) on Ge substrates are a typical gate insulator dielectric used in Ge channel metal-oxide semiconductor field-effect transistor (MOSFET) devices. As Joule heating in the Ge channel alters the MOSFET performance, the thermal transport properties of ALD-Al2O3 films and interfaces between Al2O3 and Ge have become important characteristics. This study measures the thermal transport properties of Al2O3 films on Ge substrates using the thermo-reflectance method. The thermal conductivity кm of the Al2O3 films and the thermal resistivity of the Al2O3/Ge interface were estimated to be 0.83 W m−1 K−1 and 2.8 × 10−8 m2 K W−1, respectively. A significant reduction from the thermal conductivity of crystalline Al2O3 (46 W m−1 K−1) and the large thermal resistivity of the interface were observed. To understand the thermal transport mechanism in the ALD-Al2O3 film, thermal transport was simulated using phonon-based and diffuson theories. It was found that diffuson theory was better at explaining the relatively low thermal conductivity of ALD-Al2O3. The thermal resistivity of the Al2O3/Ge interface was discussed in comparison with that of SiO2/Si interface. The improved understanding of the thermal transport properties of the ALD-Al2O3/Ge stacking structures is essential to obtain the correct prediction of the electrical performance of the MOSFET devices.

The impact of channel flattening process, dozen digital etching (DDE), which is several dozen cyclic treatments of plasma oxidation and oxide wet etching, on device performance and reliability of Ge(1 0 0) nMOSFETs has been systematically investigated. It was found that DDE improves not only electron mobility but also Positive Bias Temperature Instability (PBTI). The PBTI degradation was found related to the pre-existing bulk traps inside gate stack instead of interfacial traps generation. DDE is considered a promising technique for constructing ultra-scaled Ge 3D channel architecture such as nanowire or nanosheet for high performance CMOS devices.

Bilayer WSe2/MoSe2 van der Waals heterostructures have been directly grown on SiO2/Si substrates by 2-step chemical vapor deposition method. Bilayer nature with well aligned in-plane crystal orientation has been confirmed by Raman and transmission electron microscopy characterizations. Back gate transistors having bilayer WSe2/MoSe2 in the source side have been fabricated and high on/off ratio larger than 106 have been obtained. Gate-induced modulation of electron direct tunneling from source metal to the bottom MoSe2 layer and band to band tunneling from the valence band of WSe2 to the conduction band of MoSe2 can be an operation mechanism. Thanks to the drastic reduction of contact resistance due to the change of electron injection configuration, from edge to area injection at the source electrode, much higher on/off ratio with steeper switching was obtained in the WSe2/MoSe2 bilayer device as compared with the monolayer MoSe2 and WSe2 devices.

InGaAs photo field-effect transistors (PhotoFETs) integrated on a half-inch Si wafer have been demonstrated by means of layer transfer technology. According to the Raman measurement and scanning transmission electron microscopy (STEM), the InGaAs layer was transferred onto the half-inch Si wafer without degradation of crystal quality or introduction of strain. The optical performance of InGaAs photoFETs on Si, operating in shortwave infrared (SWIR) region was also investigated. The photoFETs on Si wafer show a responsivity of ~3 A/W at SWIR of 1550 nm with investigated range of bias. These results demonstrate InGaAs layer transfer technology is suitable for SWIR detectors on CMOS compatible platforms for monolithic integration.

Advanced channel formation technologies, such as precise control of GeOI body thickness (T body ), surface roughness and interfacial quality, utilizing Si-passivation/Ge-channel/SiGe hetero-epitaxy and Ge digital etching (DE) techniques were implemented for UTB GeOI structure. Si passivation for Ge/BOX interface has been verified to suppress Coulomb scattering owing to better interfacial quality. Insertion of SiGe etching stop (ES) layer and dozens DE (DDE) were found to be quite effective to reduce T body fluctuation as well as surface roughness, resulting in the significant improvement of mobility. As a result, we have demonstrated record high hole mobility of ~200 cm2/Vs in UTB GeOI pMOSFETs without the strain technology, which outperforms Si universal mobility by 2 times even under T body of 9 nm.

Ultra-thin-body (UTB) germanium-on-insulator (GeOI) substrates have been fabricated utilizing advanced HEtero- Layer-Lift-Off (HELLO) technology. HELLO technology is effective in mitigating thickness fluctuation issue in UTB GeOI during Ge thinning process. As a result, well-known hole mobility degradation while scaling body thickness (t body ) in UTB GeOI pMOSFETs has been suppressed. The mechanism of enhanced hole mobility in UTB GeOI pMOSFETs was also investigated through low temperature electrical measurement. The hole mobility in 9-nm-thick GeOI devices fabricated with HELLO technology showed larger temperature dependence, indicating the release of thickness fluctuation scattering.

We have demonstrated position controlled CVD growth of metal dichacogenide (WS 2 and SnS 2 ) by using patterned Si substrates. It was found that step edges effectively induced crystal nucleation and lateral crystal growth of 2D materials proceeded from there. Gas source CVD system applicable to industrial production has also been developed and WS 2 and SnS 2 synthesis have been confirmed.

Terahertz wave of 1.0 THz using ground-signal-ground (GSG) THz probe was detected by InAs quantum-well (QW) MOSHEMT. The clear response curves were obtained by the detector of which DC source (ground) terminal unconnected to the ground line of GSG THz probe. The responsivity of 10,755 kV/W with lock-in amplifier gain was achieved and noise equivalent power (NEP) of 156 pW/Hz0.5 was estimated.

Among the different Science, Technology, Engineering, and Math fields, engineering continues to have one of the highest rates of attrition (Hewlett et al., 2008). The turnover rate for women engineers from engineering fields is even higher than for men (Frehill, 2010). Despite increased efforts from researchers, there are still large gaps in our understanding of the reasons that women leave engineering. This study aims to address this gap by examining the reasons why women leave engineering. Specifically, we analyze the reasons for departure given by national sample of 1,464 women engineers who left the profession after having worked in the engineering field. We applied a person-environment fit theoretical lens, in particular, the Theory of Work Adjustment (TWA) (Dawis and Lofquist, 1984) to understand and categorize the reasons for leaving the engineering field. According to the TWA, occupations have different “reinforcer patterns,” reflected in six occupational values, and a mismatch between the reinforcers provided by the work environment and individuals’ needs may trigger departure from the environment. Given the paucity of literature in this area, we posed research questions to explore the reinforcer pattern of values implicated in women’s decisions to leave the engineering field. We used qualitative analyses to understand, categorize, and code the 1,863 statements that offered a glimpse into the myriad reasons that women offered in describing their decisions to leave the engineering profession. Our results revealed the top three sets of reasons underlying women’s decision to leave the jobs and engineering field were related to: first, poor and/or inequitable compensation, poor working conditions, inflexible and demanding work environment that made work-family balance difficult; second, unmet achievement needs that reflected a dissatisfaction with effective utilization of their math and science skills, and third, unmet needs with regard to lack of recognition at work and adequate opportunities for advancement. Implications of these results for future research as well as the design of effective intervention programs aimed at women engineers’ retention and engagement in engineering are discussed.

Electron mobility of ultra thin body (UTB) GeOI «MOSFETs with body thickness (T body ) down to 3 nm has been systematically investigated and significant mobility enhancement with decreasing T body has been observed for the first time. This channel thickness scaling induced mobility enhancement can be attributed to the unique physical property of ultra thin Ge where the electron effective mass reduces with scaling T body through the band structure modification.

Ion implantation after germanidation (IAG) technique has been implemented for low thermal budget bulk Ge and UTB-GeOI n- and p-MOSFETs. Dopant segregation at NiGe/Ge interface by low temperature drive-in annealing has an advantage in forming an abrupt metallic source/drain (S/D) junction, which is not only effective for bulk Ge but also for UTB-GeOI substrate. IAG technique is proved to be a low thermal budget process for both Ge n- and p-MOSFETs with a high I on -I off ratio and low parasitic resistance.

Terahertz wave was detected in 1.0 THz using InAs MOS-HEMT as a non-biased (cold) FET power detector at room temperature. Terahertz power detector was fabricated on quartz glass substrate by direct-wafer-bonding technique. 1.0 THz signal power was directly input to the gate terminal with drain coupling in MOS-HEMT detector through the GSG THz probe. The high responsivity of around 60 V/W was achieved at the bias voltage of −0.4 V.

Aquaculture is an economically important activity for maritime countries. However, the spread of infectious diseases among aquaculture species have a serious impact on this industry. Therefore, the early detection of pathogens is crucial for protecting aquaculture species with a premium commercial value. This study reports an integrated microfluidic system for the rapid detection of aquaculture pathogens. In this new device, the DNA (deoxyribonucleic acid) of the target pathogen was first isolated by magnetic beads coated with specific nucleotide probes after cell lysis. Then the extracted DNA fragments were amplified by the loop-mediated isothermal amplification (LAMP) process and the amplified products were detected optically. This device contained normally closed microvalves, micropumps, LAMP reaction chambers and wash units such that the entire process for isolation of pathogen DNA, nucleic acid amplification and optical detection was performed automatically in the developed microfluidic system. Experimental data showed that the developed system can automatically complete the entire process within 65 min with a detection limit of 20 copies. Another advantage of this device is that the chip is comprised of four identical modules. Therefore, this device could carry out detection of four different pathogens simultaneously. In this study, four pathogens common to cultured ornamental fishes, namely Streptococcus agalactiae, koi herpes virus, Iridovirus and Aeromonas hydrophila were analyzed by this integrated device. This device successfully completed four simultaneous detections from infected fishes in a short period of time. Compared to previous studies, this microfluidic system could complete all processes involved in pathogen detection including sample pre-treatment, nucleic acid amplification and optical detection without any manual operation. As a whole, the developed microfluidic system is promising for rapid isolation and detection of aquaculture pathogens.

The purpose of this study is to explore creative color teaching activities and their value in education. To understand the teaching method used in color science in university foundation design courses and to lead students to comprehend their own culture in application of design, the study explores solutions and strategies from the perspective of the curriculum. The study is based on the concept of action research used in a course the researcher conducted for half a semester. This study proposes to develop the color sensitivity of students, and to inspire their cultural consciousness for creative color ombination. The conclusion has three principal aspects. First, for curriculum design, the course should integrate issues to explore culture. Students could search for the mark of culture in daily life and flexibly apply their five senses to enhance their observation in color exploration and materials application. Second, for teacher tutorial, teachers should encourage hinking in every step and provide comments or direction. Teachers could implement teamwork activities to motivate the students to be inspired in their creativity. Third, for student learning, in observing culture, self-examination and group participation are essential tools in discussion. Feedback can motivate students to learn, encourage diversity in their abilities, and reach a wider field. The research suggests that chromatics foundation curriculum design should emphasize the importance of course structure and the combination of activities. Connecting the local color survey properly could raise the capability in analyzing a larger project. Moreover, self-examination transforms into the sensibility of cultural aesthetics, and develops the sense of good taste. It arouses the strength of color application, broadens range of knowledge and depth in professional development. Eventually, the learner can develop practical design talents in color acuity and observation.

Toward terahertz applications, we fabricated InGaAs layer on quartz glass by using direct-wafer-bonding technique and demonstrated InGaAs FETs performances to confirm the device fabrication process. Well-behaved FET characteristics on quartz glass have been achieved such as the maximum transconductance (g mmax ) of 69.5 mS/mm at V d = 1.5 V in InGaAs MOSFET and was 244 mS/mm at V d = 1 V in InGaAs MOS-HEMT for 1 µm gate length device. The cut-off frequencies (ƒT) of InGaAs MOSFET and MOS-HEMT of 8 GHz and 22 GHz respectively, were obtained on quartz glass.

Loop-mediated isothermal amplification (LAMP) is a nucleic acid amplification technique which amplifies DNA with high specificity, efficiency and rapidity under isothermal conditions. In this study, a microfluidic droplet-array chip is presented to implement array-based digital LAMP analysis. The proposed microfluidic system can perform the basic operation of droplets including droplet formation, droplet immobilization, LAMP and detection. This is the first time that an emulsion-droplet microfluidic device was used for array-based digital LAMP analysis. When compared to micro-well digital PCR assays, this droplet array-based digital LAMP assay eliminates the constraint on the size of the digitized target, which was determined by the dimension of the micro-wells. Moreover, the employment of hydrodynamic trapping allows for one-droplet-to-one-trap operation. This microfluidic chip may become a promising device for digital LAMP based diagnosis.

Digital loop-mediated amplification (LAMP) is an isothermal, quantitative DNA amplification approach which has high sensitivity and specificity and could be used to analyze extremely low amount of DNA within a short period of time. In this study, an integrated self-driven microfluidic chip was proposed herein for performing a digital LAMP process for vancomycin-resistant Enterococcus (VRE) diagnosis. The entire bacterial diagnosis could be automatically performed by capillary forces through the new polydimethylsiloxane (PDMS) surface treatment without using external pumps. Moreover, digitized droplets could be separated from each other by normally-close valves such that it could be quantitated. The contact angle of the treated PDMS surface was measured to be only 24°, which was the lowest value in literatures. This is the first time that a rapid (within 1 hour), simple, and hydrophilic PDMS surface modification method has been reported, which could be used in self-driven microfluidic devices for digital LAMP. This device may become a promising tool for clinical diagnosis and point-of-care applications.

Ultra-thin germanium-tin on insulator (GeSnOI) structure on Si substrate has been fabricated using the direct bonding and substrate etching techniques. This process involves the growth of GeSn layer on Ge (001) substrate followed by the deposition of ALD-Al2O3 on GeSn layer, the bonding of GeSn/Ge (001) substrate to a SiO2/Si substrate, and the removal of the Ge substrate. Using the bevel substrate etching technique, we prepared different GeSnOI structures, whose thicknesses gradually varied from 50 to 0 nm, in one sample. We investigated the thickness dependence of the material quality of the fabricated structure via micro-Raman spectroscopy; the strong Ge–Ge peaks are observed in a few nm thick GeSnOI structure, suggesting high quality of the fabricated GeSnOI structure and the enhancement of Raman intensity of the Ge–Ge peak in the ultra-thin GeSnOI structure of thickness less than 10 nm is attributed to the quantum size effect.

JPEG 2000 is an international standard for still image compression, which is based on wavelet transformation and the Daubechies 9/7 filter adopted for lossy compression. Considering that a wavelet filter might be suitable for one image but not for the other in regard to compression quality, in this paper, we propose a novel filter design framework based on the Daubechies 9/7 filter, which employs chaos evolution programming (CEP) to optimize the wavelet filter for both the universal images and each specific image, respectively. The customized filter design is ready to incorporate into the JPEG 2000 compression/decompression since the filter coefficients can be constructed by only one tuning parameter, which can be easily packaged into the modified JPEG 2000 header. Experimental results show that CEP-trained filters achieve higher image quality.

Objective Few studies address quality of care in pay-for-performance (P4P) programs from the perspective of patients' perceptions. This study aimed to examine and compare the patient assessment of diabetes chronic care as perceived by diabetic patients enrolled and not enrolled in a P4P program from the patients' self-reported perspectives. Design A cross-sectional study with case and comparison group design. Setting A large-scale survey was conducted from February to November 2013 in 18 healthcare institutions in Taiwan. Participants A total of 1458 P4P ( n = 1037) and non-P4P ( n = 421) diabetic patients participated in this large survey. The Chinese version of the Patient Assessment of Chronic Illness Care (PACIC) instrument was used and patients' clinical outcome data (e.g. HbA1c, LDL) were collected. Intervention None. Main Outcome Measures Five subscales from the PACIC were measured, including patient activation, delivery system design/system support, goal setting/tailoring, problem solving/contextual and follow-up/coordination. Patient clinical outcomes were also measured. Multiple linear regression and logistic regression models were used and controlled for patient demographic and health institution characteristics statistically. Results After adjusting for covariates, P4P patients had higher overall scores on the PACIC and five subscales than non-P4P patients. P4P patients also had better clinical processes of care (e.g. HbA1c test) and intermediate outcomes. Conclusions Patients who participated in the program likely received better patient-centered care given the original Chronic Care Model. Better perceptions of diabetic care assessment also better clinical outcomes. The PACIC instrument can be used for the patient assessment of chronic care in a P4P program.

Rapid and accurate diagnosis of C-reactive protein (CRP) is crucial for preventing cardiovascular diseases because it is a well-known biomarker for evaluating risks of cardiovascular diseases. Our previous work has shown that a microfluidic system equipped with a field-effect-transistor (FET)-based biosensor could detect CRP in 0.1X PBS and provided a limit of detection (LOD) of 26 pM CRP without gate bias. To improve the LOD, a new microfluidic device with a new methodology for measuring FET-based biosensors is presented in this study. Not only can the proposed system work in a solution with a physiological salt concentration but it also detects CRP with ultra-high sensitivity in an automatic fashion. This is the first time that a FET-based biosensor can effectively and automatically detect CRP in a physiological salt concentration without decreasing the sensitivity. The LOD of CRP using aptamer-immobilized AlGaN/GaN high-electron-mobility transistors (HEMTs) was experimentally found to be 1fM, demonstrating the superior performance of this new technique. It may be used as a point-of-care device for CRP detection in the near future.

Genome instability, metabolic switch, and activating metastasis are three of the cancer hallmarks, which always collectively contribute to cancer malignancy. We identified methylthioadenosine phosphorylase (MTAP) as a metastasis suppressor in a series isogenic lung cell lines with different invasion ability by array CGH. Using siRNA silencing and ectopic expression of MTAP, we found that MTAP not only inhibited invasion and colony forming in vitro, but also reduced metastasis and tumorigenesis in vivo. Clinically, patients with low MTAP expression associated with poor overall survival and progression-free survival. Furthermore, the metabolite analysis of clinical specimens showed that low MTAP expression leads to MTA substrate accumulation and product decrease. MTA accumulation in MTAP knockout cells reduced the level of symmetric arginine dimethylation of proteins. By using LC/MS, we identified a novel methyl-protein, whose level is elevated in MTAP knockout cells with the depletion of symmetric arginine dimethylation. Functionally, the unmethylated protein would be protected from proteolysis via caspase 3 cleavage. Moreover, the unmethylated mutant protein promoted migration and invasion in vitro strongly than the wild-type one did. In conclusion, we identify a novel marker in low MTAP expression or MTAP knockout cells, providing a potential therapeutic candidate in lung adenocarcinoma. Citation Format: Wen-Hsin Chang, Bing-Ching Ho, Kang-Yi Su, Jian-Wei Chen, Reen Wu, Pan-Chyr Yang, Sung-Liang Yu. MTAP insufficiency promotes metastasis in lung cancer via diminishing protein dimethylation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1544. doi:10.1158/1538-7445.AM2017-1544

We present the HEtero-Layer Lift-Off (HELLO) technique to obtain ultra thin body (UTB) Ge on insulator (GeOI) substrates. The transferred ultra thin Ge layers are characterized by the Raman spectroscopy measurements down to the thickness of ∼1 nm, observing a strong Raman intensity enhancement for high quality GeOI structure in ultra thin regime due to quantum size effect. This advanced Ge layer transfer technique enabled us to demonstrate UTB-GeOI nMOSFETs with the body thickness of only 4 nm.

Ultra-thin-body (UTB) germanium-on-insulator (GeOI) substrates with Si-passivated back interfaces have been fabricated by using advanced epitaxial-lift-off (ELO) technology. Performance of UTB GeOI p-MOSFETs with body thickness (T body) in the 4–16 nm range has also been characterized. Si-passivated back interfaces have been fabricated and found to be effective in mitigating the unpleasant hole-mobility degradation in the UTB GeOI regime owing to the suppression of the back interface scattering.

We fabricated Ge-on-insulator monocrystalline nanolayers with thickness H = 1–18 nm using SiO2 substrate and studied their Raman spectra. The spectra display longitudinal optical (LO) phonon and confined acoustic phonon bands. For H

Early detection of pathogens in high-value agricultural species is crucial. Therefore., many methods which can detect agricultural pathogens to prevent economic loss have been developed. Among them., immunoassays., nucleic acid hybridization and polymerase chain reaction have been demonstrated to detect pathogens in Phalaenopsis orchid successfully with satisfactory sensitivity and specificity. However., above-mentioned methods all have some disadvantages including lengthy process or requiring specialized laboratory facilities and well-trained technicians. The current study therefore presents an integrated micro fluidic system for rapid and automatic detection of pathogens in agricultural species. The entire procedure., including pathogen-specific ribonucleic acid (RNA) purification., nucleic acid amplification using reverse transcription loop-mediated-isothermal-amplification (RT-LAMP) and optical detection., can be automatically performed on a single chip within 65 minutes. Moreover., the detection module can be interchanged between a fluorescent detector and a turbidity detector., depending on the need of the operator. Furthermore., the developed system can detect pathogens directly from fresh agriculture tissues such as leaves and flowers of the Phalaneopsis orchids. This is the first time that an interchangeable integrated micro fluidic system for the detection of Phalaneopsis orchids has been demonstrated. Some of the most prevalent Phalaenopsis orchid pathogens., such as Cymbidium mosaic virus (CymMV) and Tomato spotted wilt virus (TSWV) for Phalaneopsis orchids were used in the current study to demonstrate the capabilities of the developed system. It is concluded that this system with dual detection units can directly detect pathogens from crude agricultural materials successfully.

Two new n-type diimidazolylstilbenes as blue-fluorescent dopant materials are synthesized and characterized. Blue-fluorescent devices based on these two compounds as the dopants reveal outstanding external quantum efficiencies (EQEs) (current efficiencies) of 7.8% (10.4 cd A(-1) ) and 7.7% (7.9 cd A(-1) ) with Commission internationale de l'Eclairage (CIE) co-ordinates of (0.14, 0.15) and (0.15, 0.11).