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Mg-rich monzodiorite are found in the Budongla gold ore district, Zhongba County, Xizang (Tibet) Autonomous Region, P.R. China. Studying the petrogenesis of this intermediate pluton can provide effective information to explore the geological evolution of the Lhasa terrane. One monzodiorite sample yielded a weighted mean 206Pb/238U age of 92.7 ± 1.1 Ma (mean square weighted deviation=0.33) using LA-ICP-MS zircon U-Pb dating, which represents the late phase of Late Cretaceous magmatism. The rock-forming minerals in the Budongla Mg-rich monzodiorite mainly include K-feldspar, plagioclase, quartz, biotite augite, and amphibole, and its accessory minerals mainly include magnetite, titanite, zircon, and apatite. The rocks are rich in K2O+Na2O and K2O with medium contents of SiO2, CaO, and A12O3,, suggesting these rocks belong to the high-K calc-alkaline series. These rocks have high MgO, Fe2O3, and FeO, with high Mg# values and low DI, which implies they are Mg-rich intermediate intrusive rocks. The rocks are enriched in LREEs and LILEs and depleted in HREEs and HFSEs. They have negative Eu anomalies, no obvious negative Ce anomalies, and slightly negative εHf(t). We infer that the Budongla pluton is a high-K calc-alkaline metaluminous Mg-rich monzodiorite and intruded during the post-collisional period of the Lhasa and Qiangtang terranes.

Indium-gallium-zinc oxide thin film transistor(IGZO-TFT) was fabricated using N2O plasma treated SiNx film as gate insulator and room-temperature deposited IGZO film as active layer.Comparing with the conventional IGZO-TFT,the saturation mobility increased from 4.5 to 8.1 cm2·V-1·s-1,threshold voltage reduced from 11.5 to 3.2 V,threshold swing varied from 1.25 to 0.9 V/dec.The trap states in the N2O plasma treated IGZO-TFT is obviously smaller than that in the conventional IGZO-TFT.Our results indicate that using N2O plasma treated SiNx film as gate insulator is an effective approach for improving IGZO-TFT performance.

Efficient inverted top-emitting organic light-emitting diode(ITOLED) using a thin Cs2CO3 layer modified Al as the reflective bottom cathode is demonstrated.With tris-(8-hydroxy-quinoline) aluminum(Alq3) as emitting layer and MoO3/Ag as semitransparent anode,the Al/Cs2CO3 based ITOLED shows a tune-on voltage of 3.6 V,luminance efficiency of 9.8 cd/A and 3.4 lm/W,which are much better than those(4.2 V,8.6 cd/A,2.85 lm/W) obtained from Mg∶Ag based ITOLED and those(5 V,5.5 cd/A,1.57 lm/W) obtained from bare Al based ITOLED.Electron-only devices research shows that a stronger electron-injection is obtained from Al/Cs2CO3 than Mg∶Ag and Al,which is attributed to the lower work function of Al/Cs2CO3 than Mg∶Ag and Al.The good performance of Al/Cs2CO3 based ITOLED is attributed to the efficient electron injection from the Al/Cs2CO3 cathode as well as a microcavity effect.

The bottom gate thin-film transistors(TFTs) with un-annealed and annealed ZnO film as a channel layer were fabricated.Compared with the un-annealed device,the performance of the device with annealed ZnO had been improved.The saturation mobility increased from 2.3 to 3.12 cm2/(V·s),the threshold voltage reduced from 20.8 to 9.9 V,the threshold swing varied from 2.6 to 1.9 V/dec,and the threshold voltage shifted from 8.0 to 3.4 V after applying a gate bias stress of 25 V for 3 600 s.The experimental results indicate that using annealed ZnO film as channel layer is an effective approach for improving ZnO-based TFT performance and bias stress stability.

Bottom-gate ZnO thin-film transistors(ZnO-TFTs) were fabricated with Ta2O5 film as the insulator.Ta2O5 film was grown by the radio-frequency magnetron sputtering at room temperature.The thickness of the Ta2O5 layers were 100,85,60,40 nm separately.The effect of the thickness on the performance of the ZnO-TFTs was studied.With the thickness of the insulator decreased from 100,85,60 nm to 40 nm,the field effect mobility increased from 50.5,59.3,63.8 to 71.2 cm2/V·s.The surface morphology of the Ta2O5 films were checked by the atomic force microscope,which showed that the root mean square(RMS) of the Ta2O5 films roughness decreases with decreasing the insulator thickness.The Ion/Ioff ratio and the threshold voltage are changed with the insulator thickness.

By doping red dye 4-dicyanomethylene-2-(tert-butyl)-6-methyl-4H-pyran(DCJTB) in the tris-(8-hydroxyquinolinato) metal Mq3(where M=Al, Ga, In) chelate complexes, a series of red-dopant organic light-emitting diodes with different doping concentrations have been fabricated. The electroluminescence efficiency of these red diodes with a DCJTB doped Mq3 emitting layer is found to be decreased markedly with the increasing of doping concentration. Electroluminescence characteristics of these devices are studied in terms of energy levels matching of red-dopant with the host materials and carrier transporting layers.

In order to compare two kinds of blue electroluminescent materials, we have investigated two kinds of blue OLEDs with the similar structrue ITO/CuPc/NPB/JBEM: perylene/Alq/Mg:Ag [device(J)] and ITO/CuPc/NPB/DPVBi: perylene/Alq/Mg:Ag [device (D)]. The difference of luminance and efficiency was not obvious for the two devices. However, there was remarkable difference for their lifetime. The device(J) achieved longer half lifetime of 1035 h at initial luminance of 100 cd/m2, and that of device(D) was only 255 h. According to their energy level diagrams, the difference of their stability may originate from different host materials in the two devices. It may be attributed to the better thermal stability of JBEM molecules than that of DPVBi. It is shown that JBEM may be a promising blue organic electroluminescent material with great stability.

A white organic light emitting diode (OLED) has been constructed by employing a new blue material and a red dye directly doped in the blue emitting layer. For comparison, another white cell with a blocking layer has also been made. The configurations of the devices are ITO/CuPc/NPB/JBEM(P):DCJT/Alq/MgAg (device 1) and ITO/CuPc/NPB/TPBi:DCJT/Alq/MgAg (device 2) where copper phthalocyanine (CuPc) is the buffer layer, N,N'-bis-(1-naphthyl)-N,N'-diphenyl-1.1'bipheny1-4-4'-diamine (NPB) is the hole transporting layer, 9,10-bis(3'5'-diaryl)phenyl anthracene doped with perylene (JBEM(P)) is the new blue emitting material, N,arylbenzimidazoles (TPBi) is the hole blocking layer, tris(8-quinolinolato)aluminium complex (Alq) is the electron transporting layer, and DCJT is a red dye. A stable and current independent white OLED has been obtained in device 1, which has a maximum luminance of 14 850 cd m-2, an efficiency of 2.88 Lm W-1, Commission Internationale de l'Eclairage coordinates of x = 0.32, y = 0.38 between 4-200 mA cm-2, and a half lifetime of 2860 h at the starting luminance of 100 cd m-2. Device 1 has a stability more than 50 times better than that of device 2.

A novel method, the so called ion-coordination reaction, was introduced to prepare nanometer-sized Mn-doped ZnS clusters stuck to a chitosan medium. A possible growth mechanism of the Mn-doped ZnS clusters in a chitosan film has been proposed. The X-ray diffraction showed that the ZnS clusters have a cubic structure like bulk crystals and the cluster sizes were estimated from the diffraction linewidth to be 2–4 nm based on Scherre's equation. The emission of Mn ion was observed through band-to-band excitation of ZnS. The excitation spectrum showed a large blue shift relative to that of ZnS bulk material. The effect of Zn ion concentration on the luminescence intensity reveals that the emission efficiency of Mn ion increases with the decrease of the ZnS cluster size.

Organic light-emitting diodes (LED) with a microcavity structure and an aluminium-doped zinc oxide ZnO:Al (AZO) anode have been fabricated. Effects of microcavities on the spontaneous emission of the organic LED, such as spectral narrowing, intensity enhancement and angle dependence of the emission, have been observed. Different emission colours have been obtained by changing the thickness of the AZO layer and that of a filler layer. The wavelengths of the cavity modes can be explained on the basis of the calculated total optical thickness of the individual cavities.

Rubrene was doped into the hole transport layer of an organic thin film electroluminescent (OTFEL) device with a double-layered structure. It was found that the dopant has a profound influence on the EL characteristics - it changed the region of light emission, increased the luminescence efficiency by more than 50% and improved the device stability tenfold. The reasons for these effects are discussed based on injection theory and the energy level diagram of the device.

Copper phthalocyanine(CuPc) thin film layer was inserted between the anode indium tin oxide and the hole transport layer TPD of an organic thin film electroluminescent device with a double-layered structure. It is found that the CuPc layer greatly improves the device stability. The durability of the device with CuPc layer increases about 8 times. The fact that at a constant current density the driving voltage remains unchanged with operation time for the device with CuPc layer means that the barriers of the carriers injection are stable due to the inserted CuPc layer.

Some organic thin film electroluminescent (EL) devices with aluminium-doped zinc oxide as the hole-injecting electrode have now been manufactured. Their EL spectra and J - V and B - V characteristics have been studied in detail. The work function and ionization potential of the materials composing the devices have been measured and their energy models given. The EL performance properties have been explained well.

Blue emitting electroluminescent diode using PVCz doped with perylene and BBOT as electron transport has been constructed. The emission spectrum is a mixture of spectra of BBOT and perylene. A luminance of as high as 680 cd/m2 with lumen efficiency more then 0.028 lm/W have been obtained.

The impact excitation rates, and consequently the emission intensities, of various energy states of Tm3+ in ZnS thin-film electroluminescence (TFEL) have been quantitatively evaluated by calculating the radiative transition rates and the impact cross section, together with a Baraff distribution function of hot-electron energy. The results show that the direct impact excitation rate of the 1G4 state of Tm3+ is very small, while that of the 3F4 state is fairly large, resulting in a weak blue light intensity relative to the IR light in TFEL. Different theories of the electron distribution function are compared and discussed.

Optical absorption, emission and excitation spectra, lifetimes of 4S3/2 state and 4F9/2 state from 10K to 500K, and Raman spectra were measured for Er3+ ions in fluoride glass. The radiative transition probabilities were calculated on the basis of Judd-Ofelt theory. The nonradiative transition probabilities and the quantum efficiencies were determined by calculating the difference between the measured lifetimes and the calculated radiative transition probabilities. The temperature dependence of nonradiative transition probability was investigated using the Huang-Rhys theory of multiphonon relaxation, in which two kinds of phonons as well as the parameter s were taken into consideration. A fairly good agreement of the theoretical calculation with the experimental results has been obtained. The value of s is estimated and the effect of s is discussed.

A simplified quantitative physical model for electron transport processes in TFEL is proposed. The dissipative current, brightness waveform and charge voltage characteristics of the device can be calculated from this model. Comparison of the computer simulation with the exerimental results shows that this model is nearly satisfactory. Hence some important parameters of these devices can be obtained by computer simulation.

Energy transfer between in N , N ′-bis-(1-naphthyl)- N , N ′-diphenyl-1,1′-biphenyl-4-4′-diamine (NPB) and rubrene was investigated. The device ITO/CuPc/NPB:rubrene/blocking layer /Alq/MgAg, in which copper phthalocyanine (CuPc) is used as buffer layer, NPB as the hole transporting layer (HTL), trimer of N -arylbenzimidazoles (TPBi) [or 2–(4–biphenylyl)–5–(4–tertbutylphenyl)–1,2,3–oxadiazole(PBD) or 1,2,4–triazolederivative(TAZ)] as the blocking layer, Tris(8-quinolinolato)aluminum complex (Alq) as electron transporting layers (ETL), can not give white emitting light. White emitting light can be realized in a new device with the structure ITO/CuPc/NPB/blocking layer:rubrene/Alq/MgAg, in which rubrene is doped in blocking layer instead of in NPB. The emission spectrum of this device covers a wide range of visible region and can be adjusted by the concentration of rubrene. The white emitting devices with CIE coordinates x =0.31, y =0.32, maximum luminance 8635 cd/m 2 and luminous efficiency 1.39 Lm/w, were obtained with the blocking layer TPBi doped with 1.5% rubrene.

Organic thin film transistors (OTFTs) with modified gate insulator were demonstrated in this paper. The modified gate insulator layers consisted of SiO2 as the gate insulator and OTS ( octadecyltrichlorosilane ) or PMMA (Poly(methyl methacylate)) as the modified layer. The devices with the modified layer had field-effect mobility larger than 10-3 cm2/Vs, which was twice than that of the OTFT without modification. The on/off current ratio was increased one order of magnitude and reached more than 104. The leakage current was decreased from 10-9 A to 10-10 A. The results demonstrate that using modified gate insulators can obviously improve the performance of the OTFTs.

Tin sulfide (SnS) solar cell semiconductor thin films were prepared by an RF sputtering method. The component, crystal structure, optical properties and electrical properties of SnS films were measured. The relationship between the SnS films properties and the sputtering condition was discussed. Using Sb as a dopant and combining thermal annealing at elevated temperatures (about 400/spl deg/C), n-type SnS homojunction solar cell thin films were obtained.

We demonstrate a highly efficient inverted top-emitting organic light-emitting diode (TOLED) having stable electroluminescent spectra and color coordination with variation of viewing angles by simply tuning the resonance wavelength corresponding to the free emission of the emitter. Using a doped fluorescent emitting system, the inverted TOLED exhibits an enhanced maximum current efficiency of 19 cd/A and a power efficiency of 17 lm/W, which are much higher than those (11 cd/A and 5 lm/W) of the counterpart with normal structure, although both TOLEDs behave with similar stable electroluminescent spectra characteristics. The results indicate that we provide a simple and effective method of constructing an excellent inverted TOLED for potentially practical applications.

The electron mobilities of 4, 7-diphenyl-1, 10-phenanthroline (BPhen) doped 8-hydroxyquinolinatolithium (Liq) at various thicknesses (50–300 nm) have been estimated by using space-charge-limited current measurements. It is observed that the electron mobility of 33 wt% Liq doped BPhen approaches its true value when the thickness is more than 200 nm. The electron mobility of 33 wt% Liq doped BPhen at 300 nm is found to be ~5.2 × 10−3 cm2/(V·s) (at 0.3 MV/cm) with weak dependence on electric field, which is about one order of magnitude higher than that of pristine BPhen (3.4 × 10−4 cm2/(V·s)) measured by SCLC. For the typical thickness of organic light-emitting devices, the electron mobility of doped BPhen is also investigated.

RGB pixel generation by microcavity top-emitting organic light-emitting diodes (TOLEDs) is beneficial to both the reduction of the light loss and the improving the color purity and efficiency. Based on the multi-emitting layers, white organic light-emitting diodes (OLEDs) and microcavity TOLEDs were prepared. TOLEDs were made using Ag/ITO as the reflector and adjusting layer, Al/Ag as the semi-transparent cathode, and Alq：DCJTB/TBADN：TBPe/Alq：C545 as white light emitting layer. By adjusting the thickness of ITO, optical length of cavity the colour of the device can be changed, so the RGB tricolor devices are obtained. The peak wavelengths are 476，539 and 601nm, the commission Internationale d'Eclairage (CIE) coordinates are (0.133，0.201)，(0.335，0.567) and (0.513，0.360), and the FWHM are 32，50 and 73nm for Blue, Green and Red，respectively.

In this paper the electroluminescene of highly efficient blue dopant EBDP was in vestigated. The blue and white organic light emitting diodes with the structure: indium-tin oxide(ITO)/ copper phthalocyanine(CuPc)/N,N′-bis-(1-naphenyl)-N,N′ -biphenyl -1,1′-bipheny1-4-4′-diamine (NPB)/2-t-butyl-9,10-di-(2-naphthyl)anth racene(TBADN):EBDP/tris(8-hydroxyquinoline) aluminum(Alq3)/LiF/Al and ITO/CuPc/NPB/TBADN:EBDP: 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethylj ulolidyl-9-enyl)-4H-pyran/Alq3/LiF/Al were studied by using EBDP as b lue dopant. For the blue device, the maximum luminance was 26961cd/m2 , and its maximum efficiency was 8.29cd/A. The luminance at a current density 20 mA/cm2 was 1597cd/m2. For the white device, the maximum lu minance 32291cd/m2 and maximum efficiency 8.31cd/A,the luminance of 1 413cd/m2 at a current density 20mA/cm2 were obtained. The slow decrease of efficiency with the increase of current density indicates weak exciton-exciton annihilation, which results from the large steric hindrance due to a non-planar structure of the fluorescence dye EBDP.

Devices using red phosphorescent dye as dopant with exciton blocking layer were constructed. The device structure is ITO/CuPc/NPB/TPBi:Btp2Ir(acac)/TPBi/Alq/LiF/Al. The EL spectra, luminance-current, efficiency-current characteristics of the device have been investigated. At the CIE coordinates x=0.62，y=0.35，efficiency 2.43cd /A has been achieved. At 20mA/cm2 and 400mA/cm2, luminance is 431cd/m2 and 4798 cd/m2, respectively. The effects of the emitting layer thickness on efficiency and EL spectra of the device have been studied also. With the decrease of the emitting layer thickness, efficiency decreases and the blue band of the El spectra increases. For the thickness d2Ir(acac) HOMO energy level. For the thickness d>20nm, the decrease of the efficiency is attributed to the added invalid emitting-layer and more annihilation centers.

Multicomponent excited-state emissions from monomer, exciplex and electroplex were observed in a bilayer organic electroluminescent device with a structure of ITO/TPD(60nm)/PBD(60nm)/Al(where TPD and PBD stand for N,N′diphenylN,N′bis(3-methylphenyl)1,1′biphenyl4,4′diamine) and (2(4′biphenyl)5(4″tertbutylphenyl)1,3,4oxadiazole, respectively). The difference between the photoluminescence of this device and the TPD∶PBD equimolar evaporated films suggests that the exciplex takes place only at the interface of TPD/PBD. The Variation of electroluminescence spectra with bias indicates the different formation mechanisms and the different population of each excited state component, as well as the different dynamic recombination process of carriers in this device.

The self-trapped exciton in polymers under the electric field has been studied using a tight-binding model including the electric field, symmetry-breaking term te and electron-lattice interaction simultaneously. It is discovered that the electric field will polarize the self-trapped exciton in polymers. The polarization depends on the electric field E and te. When te≤0.1eV，self-trapped biexciton in polymers shows the characteristic of the reverse polarization, i.e., electrons move along the direction of E; however, plus charges move along the minus direction of E. The cause of the polarization has been discussed.

The effect of electric field on the luminescence and exciton in polymer is studied in two aspects: 1. In strong electric field, the exciton is dissociated into a pair of positive and negative polarons. This dissociation can quantitatively indicate the electric-field-induced luminescence quenching in electroluminescent polymer m-LPPP observed recently. 2. The π electrons in polymer possess delocalization, they are easily polarized. It is shown that the exciton in polymer has huge polarizability, which is 103 times larger than that of hydrogen atoms.

The crack-tip opening angle CTOA was studied by de Koning et al. Recently, a path-independent integral, labeled T ∗ , has been presented by Brust et al. In this paper, the local field variables \ gs, \ ge p and w p in the vicinity of a stably growing crack-tip are calculated. It is found that the curves of both CTOA vs Δa and T ∗ vs Δa have the same trend as the curves of δ vs Δa , ϵ p vs Δa and w p vs Δa . The relationship between T ∗ and both of J and A p (plastic zone area) has been obtained. This relationship delineates the energy dissipated in geometry-dependent plastic deformation remote from the crack-tip. The relationships between CTOA and \ ge p or w p as well as between T ∗ and both of \ gs and \ ge p have been investigated. On the basis of these results, a new parameter controlling crack growth, i.e. effective energy release rate g has been suggested, and then the T ∗ / CTOA two-parameter criterion has been derived. The energy dissipated in direct fracture-related processes near the crack-tip may be delineated by this criterion, and then the criterion may be the most promising for elastic-plastic fracture.