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排序方式: 共有1002条查询结果,搜索用时 31 毫秒
1.
L. Gao P. Hrter Ch. Linsmeier J. Gstttner R. Emling D. Schmitt-Landsiedel 《Materials Science in Semiconductor Processing》2004,7(4-6):331
Deposition of Ag films by direct liquid injection-metal organic chemical vapor deposition (DLI-MOCVD) was chosen because this preparation method allows precise control of precursor flow and prevents early decomposition of the precursor as compared to the bubbler-delivery. Silver(I)-2,2-dimethyl-6,6,7,7,8,8,8-heptafluoro-3,5-octanedionato-triethylphosphine [Ag(fod)(PEt3)] as the precursor for Ag CVD was studied, which is liquid at 30 °C. Ag films were grown on different substrates of SiO2/Si and TiN/Si. Argon and nitrogen/hydrogen carrier gas was used in a cold wall reactor at a pressure of 50–500 Pa with deposition temperature ranging between 220 °C and 350 °C. Ag films deposited on a TiN/Si diffusion barrier layer have favorable properties over films deposited on SiO2/Si substrate. At lower temperature (220 °C), film growth is essentially reaction-limited on SiO2 substrate. Significant dependence of the surface morphology on the deposition conditions exists in our experiments. According to XPS analysis pure Ag films are deposited by DLI-MOCVD at 250 °C by using argon as carrier gas. 相似文献
2.
GaN-MOCVD设备反应室流场的CFD数值仿真 总被引:11,自引:2,他引:9
采用计算流体力学方法对生长半导体材料GaN的重要设备MOCVD(金属有机物化学气相沉积)反应室中的流场结构进行了三维数值仿真.数值模拟采用基于非交错网格系统的SIMPLE算法,用有限体积方法对控制方程进行离散,并采用改进的压力-速度耦合方法进行求解.数值仿真给出了具有复杂几何结构和运动方式的GaN-MOCVD反应室中的流场结构,研究了改变几何尺寸和运行参数对MOCVD反应室流场结构的影响,对正在试制开发中的MOCVD设备的几何结构的改进和运行参数的优化提出了指导性建议. 相似文献
3.
Zs. T
kei D. Kelleher B. Mebarki T. Mandrekar S. Guggilla K. Maex 《Microelectronic Engineering》2003,70(2-4):358-362
Passivated single damascene copper SiO2 damascene lines were evaluated in combination with TiSiN and Ta(N)/Ta diffusion barriers. Leakage current, breakdown and time-dependent dielectric breakdown properties were investigated on a wafer level basis for temperatures ranging between room temperature and 150 °C. It is found that the leakage performance of the wafers with a TiSiN barrier is better at room temperature, but at 150 °C the performance levels out with Ta(N)/Ta. Time-dependent dielectric breakdown measurements at 150 °C show that the lifetime of the interconnect is higher with the selected Ta(N)/Ta barrier than for TiSiN. 相似文献
4.
介绍了当前国际上流行的用半导体可饱和吸收镜来对固体激光器、光纤激光器和半导体激光器进行被动锁模的方法,阐述了半导体可饱和吸收镜用来作为被动锁模吸收体的原理,并介绍了如何利用金属有机气相淀积(MOCVD)技术生长各种波长激光器所需要的半导体可饱和吸收镜. 相似文献
5.
6.
高质量ZnO薄膜的退火性质研究 总被引:3,自引:0,他引:3
在LP-MOCVD中,我们利用Zn(C2H5)2作Zn源,CO2作氧源,在(0002)蓝宝石衬底上成功制备出皮c轴取向高度一致的ZnO薄膜,并对其进行500℃-800℃四个不同温度的退火。利用XRD、吸收谱、光致发光谱和AFM等手段研究了退火对ZnO晶体质量和光学性质的影响。退火后,(0002)ZnO的XRD衍射峰强度显著增强,c轴晶格常数变小,同时(0002)ZnOX射红衍射峰半高宽不断减小表明晶粒逐渐增大,这与AFM观察结果较一致。由透射谱拟合得到的光学带隙退火后变小,PL谱的带边发射则加强,并出现红移,蓝带发光被有效抑制,表明ZnO薄膜的质量得到提高。 相似文献
7.
A. Kussmaul S. Vernon P. C. Colter R. Sudharsanan A. Mastrovito K. J. Linden N. H. Karam N. H. Karam S. C. Warnick M. A. Dahleh 《Journal of Electronic Materials》1997,26(10):1145-1153
We have used spectroscopic ellipsometry to perform real-time monitoring during metalorganic chemical vapor deposition growth
of AlGaAs (on GaAs) and InGaAs (on GaAs and InP). Optical constants for these materials were obtained up to growth temperatures
of 600 to 700°C. This information permits real-time extraction of composition and layer thickness from the raw ellipsometric
data at sample rates on the order of 0.5 Hz. We describe closed-loop control of composition and total layer thickness on AlGaAs-based
structures, including Bragg reflectors. In-situ data obtained on double-heterostructure quantum-well laser structures demonstrate that spectroscopic ellipsometry is an extremely
powerful monitoring and quality-control tool, giving important real-time information on complex structures that would be difficult
and time-consuming to obtain after growth. 相似文献
8.
M. R. Islam R. V. Chelakaea J. G. Neff K. G. Fertitta P. A. Grudowski A. L. Holmes F. J. Ciuba R. D. Dupuis J. E. Fouquet 《Journal of Electronic Materials》1995,24(6):787-792
AlGaAs double heterostructures are grown by low-pressure metalorganic chemical vapor deposition to evaluate the level of oxygen
contamination in different trimethylaluminum sources. Effects of arsine purifiers, misoriented substrates, atmospheric exposure
of the growth chamber, and possible phosphorus contamination are also studied. Extensive characterization is performed on
these films by a variety of methods, including high-resolution x-ray diffraction, photoluminescence (PL), time-resolved photoluminescence,
and secondary-ion mass spectrometry. The PL intensities for structures grown with the low-alkoxide grade are reproducibly
much greater than those grown with the regular-grade TMA1. The use of AsH3 purification improves the PL intensity. 相似文献
9.
R. D. Dupuis J. C. Bean J. M. Brown A. T. Macrander R. C. Miller L. C. Hopkins 《Journal of Electronic Materials》1987,16(1):69-77
We report the results of studies which have been made on heteroepitaxial layers of GaAs and AlGaAs grown by metalorganic chemical
vapor deposition on composite substrates that consist of four different types of heteroepitaxial layered structures of Ge
and Ge-Si grown by molecular beam epitaxy on (100)-oriented Si substrates. It is found that of the four structures studied,
the preferred composite substrate is a single layer of Ge ∼1 μm thick grown directly on a Si buffer layer. The double-crystal
X-ray rocking curves of 2 μm thick GaAs films grown on such substrates have FWHM values as small as 168 arc sec. Transmission
electron micrographs of these Ge/Si composite substrates has shown that the number of dislocations in the Ge heteroepitaxial
layer can be greatly reduced by an anneal at about 750° C for 30 min which is simultaneously carried out during the growth
of the GaAs layer. The quality of the GaAs layers grown on these composite substrates can be greatly improved by the use of
a five-period GaAs-GaAsP strained-layer superlattice (SLS). Using the results of these studies, low-threshold optically pumped
AlGaAs-GaAs DH laser structures have been grown by MOCVD on MBE Ge/Si composite substrates. 相似文献
10.
R. Niebuhr K. H. Bachem U. Kaufmann M. Maier C. Merz B. Santic P. Schlotter H. Jürgensen 《Journal of Electronic Materials》1997,26(10):1127-1130
Oxygen doped GaN has been grown by metalorganic chemical vapor deposition using N2O as oxygen dopant source. The layers were deposited on 2″ sapphire substrates from trimethylgallium and especially dried
ammonia using nitrogen (N2) as carrier gas. Prior to the growth of the films, an AIN nucleation layer with a thickness of about 300? was grown using
trimethylaluminum. The films were deposited at 1085°C at a growth rate of 1.0 μm/h and showed a specular, mirrorlike surface.
Not intentionally doped layers have high resistivity (>20 kW/square). The gas phase concentration of the N2O was varied between 25 and 400 ppm with respect to the total gas volume. The doped layers were n-type with carrier concentrations
in the range of 4×1016 cm−3 to 4×1018 cm−3 as measured by Hall effect. The observed carrier concentration increased with increasing N2O concentration. Low temperature photoluminescence experiments performed on the doped layers revealed besides free A and B
exciton emission an exciton bound to a shallow donor. With increasing N2O concentration in the gas phase, the intensity of the donor bound exciton increased relative to that of the free excitons.
These observations indicate that oxygen behaves as a shallow donor in GaN. This interpretation is supported by covalent radius
and electronegativity arguments. 相似文献