GaAs基HBT材料的外延生长及其特性研究

【作者】 彭鹏；

【导师】 陈建新； 李爱珍；

【作者基本信息】 中国科学院上海冶金研究所 ， 微电子学与固体电子学， 2000， 硕士

【摘要】 本论文主要从异质结双极型晶体管（HBT）用Ⅲ—V 族化合物半导 体材料结构和分子束外延（GSMBE）生长工艺的角度，对影响材料和器 件性能的一些机理和材料结构参数进行了分析和讨论。并在理论分析和 数值模拟计算的基础上，对适用于HBT 的Ⅲ—V 族半导体微结构材料 的参数选择进行较细致的研究。并用GSMBE 生长的样品进行了工艺流片 和器件性能测量。主要内容和结果包括 1 对HBT 结构中载流子的分布进行了模拟计算，用费米统计率对 玻尔兹曼统计律进行了修正，并在热场发射──扩散模型的基础 上，对HBT 的电流特性进行了数值计算。分别讨论了发射区、基区掺杂浓度和空间间隔层厚度对器件的直流增益的影响。还 专门对 AlGaAs／GaAs 和 InGaP／GaAs 两种材料体系的δ掺杂 HBT 结构的直流特性及各电流分量进行了具体的讨论和数值计算， 并提出了一种改进的在间隔层两侧生长双δ掺杂层的结构。 2 采用以气态砷烷（AsH₃）、磷烷（PH₃）和固态Al、Ga、In 等作 为分子束源的气态源分于束外延（GSMBE）技术，研究了GaAs、 AlGaAs、InP、InGaP 等薄膜材料及其异质结构的GSMBE 的生长 与特性，为进一步进行HBT器件制作打下了良好的材料基础。 3 在我们生长的InGaP／GaAS HBT 材料基础上，进行了工艺流片， 得到了具有良好电流特性的大尺寸器件，并对HBT 器件进行了 测量，电流增益可达320。更多还原

【Abstract】 In this thesis, heterojunction bipolar transistors （HBTs） and materialswere studied theoretically and experimentally from the viewpoint of thestructural design and growth technology In addition, based on the theorycalculation and simulation, the selection of the microstructure of the Ⅲ-V compound semiconductor applied in HBT devices was studied in detail Thefabrication processing and devices properties of samples prepared by GSMBEwere investigated The results presented in this thesis can be sununarized asfollowingWe calculate the distribution of the carriers in HBTs based on Fermistatistic function And the distributlon of the carriers is compared with theresult of calculations based on Boltzmann statistic function Meanwhile, onthe basis of thermionic field-diffusion model, we study the numericalinvestigation of the current performance of HBTs The influences of dopantconcentration of emitter and base and the thickness of space layer werediscussed Particularly, we discussed and calculated the dc properties andeach current of the structure of δ-doped AlGaAs/GaAs and InGaP/GaAs materialsAn improved double δ-doped structure by growing both of the space layers wassuggestedUsing AsH₃、 PH₃ as gas sources and Al、Ga、In as solid sources, GaAs. AlGaAsand InGaP thin films were investigated by GSMBE High quality materials suchas GaAs、AlGaAs/GaAs、InGaP/GaAs were obtained by optimizing the growthcondition The resu1ts 1ndlcated that these studies would be a good foundationfor further device fabrication0n the basis of InGaP/GaAs mater1als fabricated by GSMBE, large sizeddevices with good electrical current properties were obtained Themeasurement resu1ts indicated that the current gain was up to 320更多还原