Growth of near planar Si0.5Ge0.5 epitaxial layers directly on Si substrate by UHV/CVD at 500℃

The relationship between Ge content of Si1-xGex layers and growth conditions was investigated via UHV/CVD system at relative low temperature of 500℃. Si1-xGex layers were in a metastable state in this case. 10-period strained 3.0 nm- Si0.5Ge0.5/3.4 nm- Si multi quantum wells were obtained directly on Si substrate. Raman Measurement, high resolution electron microscopy and photoluminescence were used to characterize the structural and optical properties. It is found that such relative thick Si0.5Ge0.5/Si multi quantum wells are still near planar and free of dislocations, that makes it exploit applications to electrical and optical devices.

水平冷壁CVD生长4H-SiC同质外延膜

采用自行设计的水平冷壁低压化学气相沉积(LPCVD)方法在偏向〈1120〉晶向8°的n型4H-SiC(0001)衬底上进行了同质外延生长.在5.3×103Pa的低压下,外延膜生长速率超过3μm/h.电容-电压法测试表明在非有意掺杂外延膜中净施主浓度为8.4×10 15cm-3.Nomarski显微镜观察表明厚外延膜的表面光滑,生长缺陷密度很低.AFM测试显示表面均方根粗糙度为0.3nm,没有观察到宏观台阶结构.Raman谱线清晰锐利,表现出典型的4H-SiC特征.在低温PL谱中,近带边区域出现很强的自由激子峰,表明样品是高质量的.

Improved Epitaxy of 3C-SiC Layers on Si(100) by New CVD/LPCVD System

Single crystalline 3C-SiC epitaxial layers are grown on φ50mm Si wafers by a new resistively heated CVD/LPCVD system, using SiH_4, C_2H_4 and H_2 as gas precursors. X-ray diffraction and Raman scattering measurements are used to investigate the crystallinity of the grown films. Electrical properties of the epitaxial 3C-SiC layers with thickness of 1 ～ 3μm are measured by Van der Pauw method. The improved Hall mobility reaches the highest value of 470cm~2/(V·s) at the carrier concentration of 7.7 * 10~(17)cm~(-3).

ECR plasma CVD法淀积980 nm大功率半导体激光器端面光学膜技术

介绍了电子回旋共振等离子体化学气相沉积(简称ECR plasma CVD)法淀积980nm大功率半导体激光器两端面光学膜的工艺条件，探索了膜系监控的方法和优越性，讨论了这种淀积方法的优点和淀积的光学膜的优良特性。

ECR Plasma CVD淀积光电器件介质膜的工艺模拟

于2010-11-23批量导入

UHV/CVD外延生长SiGe/Si表面反应动力学

利用SiH_4和GeH_4作为源气体，对UHV/CVD生长Si_(1-x)Ge_x/Si外延层的表面反应机理进行了研究，通过TPD、RHEED等实验观察了Si(100)表面SiH_4的饱和吸附、热脱附过程，得出SiH_4的分解应该是每个SiH_4分子的4个H原子全部都吸附到了Si表面，SiH_4的吸附率正比于表面空位的4次方，并分析了GeH_4的表面吸附机制。在此基础上建立了UHV/CVD生长Si_(1-x)Ge_x/Si的表面反应动力学模型,利用模型对实验结果进行了模拟，二者符合得很好。

UHV/CVD生长SiGe/Si异质结构材料

以Si_2H_6和GeH_4作为源气体，用UHV/CVD方法在Si(100)衬底上生长了Si_(1-x)Ge_x合金材料和Si_(1-x)Ge_x/Si多量子阱结构。用原子力显微镜、X光双晶衍射和透射电子显微镜对样品的表面形貌、均匀性、晶格质量、界面质量等进行了研究。结果表明样品的表面平整光滑，平均粗糙度为1.2nm；整个外延片各处的晶体质量都比较好，各处生长速率平均偏差3.31%，合金组分x值的平均偏差为2.01%;Si_(1-x)Ge_x/Si多量子阱材料的X光双晶衍射曲线中不仅存在多级卫星峰，而且在卫星峰之间观察到了Pendellosung条纹，表明晶格质量和界面质量都很好；Si_(1-x)Ge_x/Si多量子阱材料的TEM照片中观察不到位错的存在。

ECR Plasma CVD淀积介质膜折射率的神经网络模拟

用人工神经网络方法对电子回旋共振等离子法化学气相沉积(ECR Plasma CVD)镀膜工艺建立了一个介质膜折射率n关于气流配比Q(N_2)/Q(SiH_4)和Q(Q_2)/Q(SiH_4)的数学模型。在给定气流配比Q(N_2)/Q(SiH_4)和Q(O_2)/Q(SiH_4)时模型预测的成膜折射率与实验值符合得很好。

ECR Plasma CVD法淀积介质膜技术在半导体光电器件中的应用

电子回旋共振等离子体化学气相淀积(ECR Plasma CVD)法淀积介质膜技术是制备性能优良的光电子器件光学膜和电介质膜的重要手段之一。该文报道了ECR Plamsa CVD法淀积介质膜的工艺以及介质膜的特性等。

ECR Plasma CVD法淀积808nm大功率半导体激光器光学膜工艺研究

介绍了电子回旋共振等离子体化学气相沉积(简称ECR Plasma CVD)法淀积808nm大功率半导体激光器两端面光学膜的工艺，给出工艺条件，探索了膜系监控的方法和优越性，讨论了这种淀积方法的优点和淀积的光学膜的优良特性。

Comparison of GexSi1—x Grown by UHV／CVD from Si2H6／GeH4 and SiH4／GeH4

国家自然科学基金

GeSi CVD系统的流体力学和表面反应动力学模型

于2010-11-23批量导入

Type-II SiGe/Si MQWS (multi-quantum wells) and self-organized Ge/Si islands grown by UHV/CVD system

Type-II SiGe/Si MQWs (Multi-Quantum Wells) and Self-Organized Ge/Si Islands were successfully grown by a homemade ultra-high vacuum/chemical vapor deposition (UHV/CVD) system. Growth characteristics and PL (photoluminescence) spectra at different temperature were measured. It demonstrated that some accumulation of carriers in the islands results in the increase of the integrated PL intensity of island-related at a certain temperature range.

Structural evaluation of polycrystalline silicon thin films by hot-wire-assisted PECVD

Tungsten wires were introduced into a plasma-enhanced chemical vapor deposition (PECVD) system as a catalyzer: we name this technique 'hot-wire-assisted PECVD' (HW-PECVD). Under constant deposition pressure (p(g)), gas flow ratio and catalyzer position, the effects of the hot wire temperature (T-f) on the structural properties of the poly-Si films have been characterized by X-ray diffraction (XRD), Raman scattering and Fourier-transform infrared (FTIR) spectroscopy. Compared with conventional PECVD, the grain size, crystalline volume fraction (X-e) and deposition rate were all enhanced when a high T-f was used. The best poly-Si film exhibits a preferential (220) orientation, with a full width at half-maximum (FWHM) of 0.2 degrees. The Si-Si TO peak of the Raman scattering spectrum is located at 519.8 cm(-1) with a FWHM of 7.1 cm(-1). The X-c is 0.93. These improvements are mainly the result of promotion of the dissociation of SiH4 and an increase in the atomic H concentration in the gas phase. (C) 2001 Elsevier Science B.V. All rights reserved.