LiNbO_3/SiO_2/Si薄膜的蓝光发射

采用射频磁控溅射方法制备了LiNbO3/SiO2／Si薄膜。通过X射线衍射（XRD）、电感耦合等离子体质谱（ICP-MS）和傅立叶变换红外吸收光谱（FT-IR）对薄膜的物相、晶体取向和成分进行了表征。采用荧光分光光度计研究了LiNbO3／SiO2／Si薄膜的光致发光。研究结果表明：在280nm激发光的激发下,LiNbO3／SiO2／Si薄膜在室温下发射470nm的蓝光,来源于LiNbO3薄膜与SiO2层界面处白捕获激子的辐射复合,发现在SiO2／Si薄膜上生长LiNbO3薄膜调制SiO2／Si薄膜的发光机制。     

AlN成核层厚度对Si上外延GaN的影响

采用低温AlN成核层,在Si(111)衬底上,用金属有机化学气相沉积(MOCVD)法生长了GaN薄膜。采用高分辨X射线衍射(XRD)、椭圆偏振光谱仪和原子力显微镜(AFM)研究了AlN成核层的厚度对GaN外延层的影响。对AlN的测试表明,AlN的表面粗糙度(RMS)随着厚度增加而变大。对GaN的测试表明,所有GaN样品在垂直方向处于压应变状态,并且随AlN厚度增加而略有减弱。GaN的(0002)_ω扫描的峰值半宽(FWHM)随着AlN成核层厚度增加而略有升高,GaN(10-12)_ω扫描的FWHM随着厚度增加而有所下降。(10-12)_ω扫描的FWHM与GaN的刃型穿透位错密度相关,A1N成核层的厚度较大时会降低刃型穿透位错密度,并减弱c轴方向的压应变状态。     

直径52～65mm探测器级Si单晶的真空制备

为了制备纯度11N以上、直 径Φ大于 45mm并且各项性能指标满足探测器级要求的大直径 超高纯单晶Si材料,本文在真空气氛下提纯并生长Φ52～65mm探测器级区熔(FZ,float zone)Si单晶, 并对真空气氛和直径增加所带来的晶体不稳定生长、高断面电阻率不均匀率和漩涡缺陷 等问题的产生原因和解决方式进行了深入研究。结果表明,丹麦加热线圈表面带有台阶 和十字开口,是提纯和生长Φ大于45mm 多晶Si和单晶Si的理想线圈;适当提高单晶转速和 生长速度有利于降低断面电阻率不均匀率,且提高转速的效果更加明显;真空气氛下, 提高热场对中性可抑制漩涡缺陷的产生,其对漩涡缺陷的影响比单晶Si生长速度更加显 著,这是与Ar气气氛FZ不同的;多晶Si提纯次数越多单晶Si寿命越低,降低多晶Si原 料中的P/B和重金属原始含量有利于提高单晶Si寿命;若要制备少子寿命大于800μs, 符合探测器级标准的Φ52～65mm Si单晶 ,多晶Si原料少子寿命应大于3000μs。     

高性能双极型集成电路晶体管

本文讨论作为集成电路元件的高性能双极型晶体管的现状和有关的工艺问题。     

Si／Si1—xGex异质结器件

本文综述了国外Si/Si_(1-x)Ge_xHBT的发展状况,把出Si_(1-x)Ge_xHBT的特点和优越性,分析了Si_(1-x)Ge_xHBT的制造技术和设备要求,指出了Si/Si_(1-x)Gex器件的应用前景。     

Low-temperature processing of shallow junctions using epitaxial and polycrystalline CoSi2

Cobalt disilicide is grown epitaxially on (100) Si from a 15 nm Co/2 nm Ti bilayer by rapid thermal annealing (RTA) at 900°C. Polycrystalline CoSi₂ is grown on (100) Si using a 15 nm Co layer and the same annealing condition. Silicide/p⁺-Si/n-Si diodes are made using the silicide as dopant source:¹¹B⁺ ions are implanted at 3.5–7.5 kV and activated by RTA at 600–900°C. Shallow junctions with total junction depth (silicide plus p⁺ region) measured by high-resolution secondaryion mass spectroscopy of 100 nm are fabricated. Areal leakage current densities of 13 nA/cm² and 2 nA/cm² at a reverse bias of -5V are obtained for the epitaxial silicide and polycrystalline silicide junctions, respectively, after 700°C post-implant annealing.     

真空微电子器件硅锥阴极的工艺研究

本文介绍了利用半导体硅材料制作的真空微电子器件的核心部件,场致发射硅锥阴极,的工艺研究及实验结果。提出了两步腐蚀的工艺方案,制成了形状理想的锥体阴极。     

采用Ti/TiW/Au栅制作Si衬底上CaAs MESFET与集成电路

本文从制备硅集成电路(SiIc)与砷化镓集成电路(GaAs IC)单片兼容电路的要求出发,提出了Ti/TiW/Au肖特基金属化结构,制备出了性能良好的Ti/TiW/Au栅Si衬底上分子束外延(MBE)的GaAsMESFET与GaAs IC。     

Deep-level transient spectroscopy of detector-grade high-resistivity float-zone silicon

In this paper, the application of standard capacitance DLTS to high-resistivity (HR) silicon is investigated both theoretically and experimentally. As will be demonstrated, typical artefacts occur, which are related to the low doping density of the material (order of a few times 10¹¹ to 10¹² cm^-3). The high series resistance of a HR-Si diode gives rise to the so-called Q-effect, yielding a reduction of the DLTS peak amplitude, which is particularly pronounced at room temperature and for p-type material. A second effect is the occurrence of non-negligible re-emission during the filling pulse, which causes the Arrhenius plot to deviate from a straight line and is particularly important for repulsive trapping centres. Methods will be discussed to reduce or correct for these phenomena. They will be illustrated by the practical example of the interstitial Fe donor-level in p-type HR-Si.     

Differences in Si doping efficiency in tertiarybutylarsine,monoethylarsine and arsine for GaAs and AlGaAs grown by MOVPE

We investigate differences in Si doping of GaAs and AIGaAs between group-V sources. Si₂H₆ and SiH₄ doping dependence on growth temperature, V/III ratio, total flow rate, growth rate, and off angle of substrate orientation was examined using tertiarybu-tylarsine (TBAs), monoethylarsine (EtAs), and arsine with a horizontal atmospheric pressure reactor. With either dopant source, Si incorporation for films grown using TBAs or EtAs was always higher than that using arsine. Using silane, dependence of Si incorporation on growth temperature and total gas flow velocity is different between group-V sources. Using disilane, dependence on V/III ratio and total gas flow velocity is different between group-V sources. These results imply that gas phase reactions play an important role. From the kinetic simulation of the decomposition of group-V sources, we verified that the concentrations of AsH₃, AsH₂, and AsH in vapor near the substrate are quite different among group-V sources. AsH₂ is dominant reactant when using TBAs. We propose that H₂AsSiH₃ (silylarsine) is formed by the reaction between AsH₂ radical and SiH₄ and silylarsine should contribute Si incorporation reactions, resulting in high Si incorporation efficiency with TBAs and EtAs. We also suggest that AsH₃ inhibits Si incorporation.