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Integration of InxGa1–xAs n-MOSFETs and SiyGe1–y p-MOSFETs could be a key to realize future low-power and high-speed logic circuits. In this paper, monolithic integration of InAs n-MOSFETs and Ge p-MOSFETs on a Si substrate is reported. To address the challenge of integrating materials with large lattice mismatch (InAs and Ge on Si substrate), a sub-120-nm GaSb-on-GaAs buffer on a germanium-on-insulator (GeOI) starting substrate is employed. The strain resulting from the 7.78% lattice mismatch between the GaSb and GaAs layers is mainly relaxed via interfacial misfits at the GaSb/GaAs interface, enabling significant reduction in the buffer thickness. For device fabrication, a self-aligned gate last process flow with Si-CMOS-compatible modules is used. To realize raised source-drain device architecture, a combination of dry and digital etch processes is developed to etch InAs and Ge cap layers. Devices with channel thicknesses less than 5 nm and channel lengths less than 200 nm are realized for both n- and p-MOSFETs, with promising electrical characteristics. [ABSTRACT FROM PUBLISHER]

We demonstrate nonvolatile and area-efficient ternary content-addressable memories (TCAMs) featuring amorphous indium–gallium–zinc–oxide (a-IGZO) ferroelectric field-effect transistors (FeFETs) with excellent electrical characteristics. An extremely large sensing margin of the TCAM array is achieved due to the large current ON/OFF ratio ($I_{ \mathrm{\scriptscriptstyle ON}}/I_{ \mathrm{\scriptscriptstyle OFF}})$ of the a-IGZO FeFETs. Our HfxZr $_{\text {1-x}}\text{O}$ 2 (HZO)-based a-IGZO FeFETs have a metal–ferroelectric–metal–insulator–semiconductor (MFMIS) structure. By engineering the area ratio of the ferroelectric layer (${A}_{Fe}$) and the metal–oxide–semiconductor layer (${A}_{MOS}$), a large memory window (MW) of 2.9 V is realized. Reliability test results, including retention, endurance, and positive bias temperature instability, show long-term retention of more than ten years and high endurance of 108 cycles. In addition, by scaling the channel length down to 40 nm, ON current of $77 ~\mu \text{A}/ \mu \text{m}$ (${V}_{\mathrm{GS}} - {V}_{\mathrm{TH}}$ = 5 V and ${V}_{\mathrm{DS}}$ = 2 V) and ${I}_{ \mathrm{\scriptscriptstyle ON}} / {I}_{ \mathrm{\scriptscriptstyle OFF}}$ of more than eight orders can be obtained for the ultrascaled a-IGZO FeFETs while maintaining an MW of 2.8 V. [ABSTRACT FROM AUTHOR]

To enable heterogeneous integration of InGaAs based transistors with Si complementary metal-oxide-semiconductor (CMOS) devices, metal contacts to n+-InGaAs need to have high thermal stability for CMOS process compatibility and ultra-low contact resistance to achieve good device performance. In this work, n+-InGaAs contacts with ultra-low contact resistivity pc based on refractory metals such as molybdenum (Mo) were realized. Use of refractory metal contacts achieves good thermal stability. An improved process that eliminates oxide between the metal and n+-InGaAs by using an in situ Ar+-plasma treatment prior to metal deposition achieves ultra-low pc. Furthermore, a nano-scale transmission line method (nano-TLM) structure with significantly reduced parasitic leakage was designed and fabricated to improve the pc extraction accuracy. The improved test structure introduces a SiO2 isolation layer between Mo and InGaAs outside the active or mesa region to eliminate a parallel leakage path that is present in other nano-TLM structures reported in the literature. [ABSTRACT FROM AUTHOR]

We investigate the effect of channel layer thickness on effective mobility (μeff) in the sub-10-nm regime of amorphous indium–gallium–zinc–oxide thin-film transistors (α-IGZO TFTs). TFT devices with extremely scaled channel thickness tα-IGZO of 3.6 nm were realized, exhibiting low subthreshold swing (SS) of 74.4 mV/decade and the highest effective mobility μeff of 34 cm2/V ⋅ s at a carrier density NCarrier of ~ 5 × 1012 cm−2 for any kind of α-IGZO TFTs having sub-10-nm tα-IGZO. No significant degradation of μeff is observed as α-IGZO thickness reduced from 6 to 3.6 nm. By scaling down the channel length LCH to 38 nm, high extrinsic transconductance (Gm, max) of 125 μs/μm (at VDS of 1 V) and ON-state current ION of 350 μA/μm at VGS – VT of 3 V with VDS of 2.5 V are achieved. [ABSTRACT FROM AUTHOR]

Germanium–tin (GeSn) p-channel fin field-effect transistor (p-FinFET) was realized on a novel GeSn-on-insulator (GeSnOI) substrate. The high-quality GeSnOI substrate was formed using direct wafer bonding technique and was layer-transferred from a 300-mm GeSn/Ge/Si donor wafer. Material quality was examined using atomic force microscopy, high-resolution transmission electron microscopy, Raman spectroscopy, and high-resolution X-ray diffraction. The fabricated GeSn p-FinFETs exhibit a small subthreshold swing (${S}$) of 79 mV/decade at ${V}_{\text {DS}}$ of −0.05 V (by a device with ${L}_{\text {CH}}$ of 200 nm and ${W}_{\text {Fin}}$ of 30 nm), good control of short channel effects, and high intrinsic transconductance (${G}_{m,\text {int}} = 702\,\,\mu \text {S}/\mu \text{m}$ at ${V}_{\text {DS}}$ of −0.5 V for ${L}_{\text {CH}}$ of 80 nm). Low-temperature mobility analysis was performed on the GeSn p-FinFETs. High effective hole mobility ($\mu _{\text {eff}}$) (210 cm2/ $\text {V}\cdot \text {s}$ at 290 K and 398 cm2/ $\text {V}\cdot \text {s}$ at 5 K) is achieved. The GeSn p-FinFETs presented in this paper exhibit the highest ${G}_{m,\text {int}}/{S}_{\text {sat}}$ at ${V}_{\text {DS}}$ of −0.5 V for all the reported GeSn p-FETs to date. [ABSTRACT FROM AUTHOR]

We report on the growth of In0.30Ga0.70As channel high electron mobility transistor (HEMT) epi-layers on a 200-mm Si substrate by metal-organic-chemical-vapor-deposition. The HEMT layers were grown on the Si substrate by using a ~3- \mu \textm thick epitaxial buffer composing of a Ge layer, a GaAs layer, and a compositionally graded and strain relaxed InAlAs layer. The optimized epitaxy has a threading dislocation density of less than 2 \times 10^7 cm−2 and a root mean square surface roughness of ~6.7 nm. The device active layers include a \delta -doped InAlAs bottom barrier, a ~15-nm thick InGaAs channel, a ~8-nm InGaP top barrier layer and a heavily doped InGaAs contact layer. MOSHEMTs with channel length down to 130 nm were fabricated. The devices achieve a peak transconductance of \sim 450 ~\mu \textS/ \mu \textm at V D of 0.5 V. The peak effective mobility ( \mu \text {eff} ) in a device with a channel length of 20 \mu \textm device channel was ~3700 cm2/ \textV \cdot \texts . [ABSTRACT FROM AUTHOR]

We report on the growth of an In0.30Ga0.70As channel high-electron mobility transistor (HEMT) on a 200 mm silicon wafer by metal organic vapor phase epitaxy. By using a 3 µm thick buffer comprising a Ge layer, a GaAs layer and an In- AlAs compositionally graded strain relaxing buffer, we achieve threading dislocation density of (1.0 ± 0.3) × 107 cm-2 with a surface roughness of 10 nm RMS. No phase separation was observed during the InAlAs compositionally graded buffer layer growth. 1.4 µm long channel length transistors are fabricated from the wafer with IDS of 70 µA/µm and gm of above 60 µS/µm, demonstrating the high quality of the grown materials. [ABSTRACT FROM AUTHOR]

Angiolipoma is one of the rare variant of lipoma. This benign tumour consists of both fatty and vascular elements. It mostly occur in the trunk and extremities and is uncommon in head and neck region. Angiolipoma is classified as infiltrating and non- infiltrating types. Among all neoplasms of the oral cavity, lipomas account for 1 to 5% and the incidence of angiolipoma is 5 to 17% in it. There is no sex predilection for this tumour. It is classified as infiltrative and non-infiltrative type. Surgical excision is the method to be considered for both the types of angiolipoma, however the infiltrating type recurs post-surgery. We report a rare case report of 55-year-old female with non-infiltrating angiolipoma of the hard palate mimicking a mucocele treated by surgical excision with no signs of recurrence and good wound healing after three months follow up with minimal scar formation. [ABSTRACT FROM AUTHOR]