基于InP衬底的GaAsSb/InP异质结晶体管

采用金属有机化学气相沉积生长了InP/GaAs0.5Sb0.5/InP 双异质结晶体三极管(DHBT)材料,研究了材料质量对器件性能的影响.制备的器件不但具有非常好的直流特性,而且还表现出良好的微波特性,其结果与能带理论的预言一致,DHBT集电结和发射结的电流理想因子分别为1.00和1.06,击穿电压高达15V,电流放大增益截止频率超过100GHz.     

GaAsSb/InAlAs PA DHBTs Grown by Production MBE

The epi material growth of GaAsSb based DHBTs with InAlAs emitters are investigated using a 4×100mm multi-wafer production Riber 49 MBE reactor fully equipped with real-time in-situ sensors including an absorption band edge spectroscope and an optical-based flux monitor.The state-of-the-art hole mobilities are obtained from 100nm thick carbon-doped GaAsSb.A Sb composition variation of less than ±0.1 atomic percent across a 4×100mm platen configuration has been achieved.The large area InAlAs/GaAsSb/InP DHBT device demonstrates excellent DC characteristics,such as BV_CEO＞6V and a DC current gain of 45 at 1kA/cm2 for an emitter size of 50μm×50μm.The devices have a 40nm thick GaAsSb base with p-doping of 4.5E19cm-3.Devices with an emitter size of 4μm×30μm have a current gain variation less than 2% across the fully processed 100mm wafer.f_t andf_max are over 50GHz,with a power efficiency of 50%,which are comparable to standard power GaAs HBT results.These results demonstrate the potential application of GaAsSb/InP DHBT for power amplifiers and the feasibility of multi-wafer MBE for mass production of GaAsSb-based HBTs.     

GaAsSb/InAlAs PA DHBTs Grown by Production MBE

The epi material growth of GaAsSb based DHBTs with InAlAs emitters are investigated using a 4 × 100mm multi-wafer production Riber 49 MBE reactor fully equipped with real-time in-situ sensors including an absorption band edge spectroscope and an optical-based flux monitor. The state-of-the-art hole mobilities are obtained from 100nm thick carbon-doped GaAsSb. A Sb composition variation of less than ± 0.1 atomic percent across a 4 × 100mm platen configuration has been achieved. The large area InAlAs/GaAsSb/InP DHBT device demonstrates excellent DC characteristics,such as BVCEO＞6V and a DC current gain of 45 at 1kA/cm2 for an emitter size of 50μm × 50μm. The devices have a 40nm thick GaAsSb base with p-doping of 4. 5 × 1019cm-3 . Devices with an emitter size of 4μm × 30μm have a current gain variation less than 2% across the fully processed 100mm wafer. ft and fmax are over 50GHz,with a power efficiency of 50% ,which are comparable to standard power GaAs HBT results. These results demonstrate the potential application of GaAsSb/InP DHBT for power amplifiers and the feasibility of multi-wafer MBE for mass production of GaAsSb-based HBTs.     

InP/GaAsSb/InP双异质结双极晶体管技术发展现状(Ⅰ)

InP/GaAsSb/InP双异质结双极晶体管(DHBT)以其独特的交错Ⅱ型能带结构,在频率特性、击穿特性和热特性等方面较传统的InP/InGaAsSHBT与InP/InGaAs/InPDHBT等显示出极大的优越性。对InP/GaAsSb/InPⅡ型DHBT技术的提出、外延层结构设计与生长、器件结构设计、器件制造工艺与优化以及国内外发展情况研究水平、发展趋势和商业化情况进行了系统的回顾和展望。指出结合垂直方向材料结构优化缩小器件尺寸和采用微空气桥隔离基极电极结构是InP/GaAsSb/InPDHBT向THz截止频率发展的最重要的技术路线。     

用于InP基DHBT制备的GaAs0.51 Sb0.49湿法腐蚀研究

介绍了采用基于柠檬酸、硫酸和磷酸的腐蚀溶液对气态分子束外延生长的InP衬底上GaAs0.51 Sb0.49湿法腐蚀研究工作.对不同体积比的腐蚀溶液的腐蚀速率和表面粗糙度进行了研究.和硫酸及磷酸基腐蚀液相比,柠檬酸/双氧水腐蚀液的腐蚀速率较慢但具有很好的表面粗糙度.作为验征,采用最优体积比5∶1的柠檬酸/双氧水腐蚀溶液,...     

发射区底切对倒置结构InP/GaAsSb/InP DHBT性能的影响

基于考虑载流子弹道输运等非局域传输瞬态效应的流体动力学模型,数值模拟计算了集电区在上面发射区在下面的倒置InP/GaAsSb/InP双异质结双极晶体管(DHBT)器件的直流输出特性和高频性能.计算结果表明:由于集电区台面面积小,集电区在上的倒置InP/GaAsSb/InP双异质结双极晶体管有较高的高频性能;对于发射区在下面与基区接触面积大导致较多的基区载流子复合而使器件的增益偏低问题,可以考虑掩埋侧边腐蚀工艺底切发射区的技术来减少发射区和基区的接触面积,从而减少复合改善器件的增益特性.     

InP DHBT技术的最新进展

阐述了目前InP DHBT器件技术的研究进展,介绍了I型InP/InGaAs DHBT技术的研究水平和Ⅱ型InP/GaAsSb DHBT技术的开发现状。综述了InP DHBT在功率放大器、分布放大器、静态分频器和压控振荡器领域的应用,指出了其在高速数据传输系统中的重要性。为了适应高速数据传输系统的飞速发展,满足10/40/100Gbit/s高速系统的技术需求,对我国研发InPDHBT技术提出初步建议。     

一种基于InP DHBT的CB Stack功率放大器设计北大核心

设计了一种中心频率为75 GHz的单级MMIC功率放大器，基于0.8μm InP DHBT器件制造，该器件ft/fmax为171/250 GHz。电路采用两层共基堆叠(CB Stack)结构，其中下层共基偏置采用基极直接接地，输入端发射极采用-0.96 V负压供电的方式，偏置电压Vc2为4 V。为了提高输出功率，上下两层器件进行了四指并联设计。此外，采用同样器件设计了另外一款下层共射的传统Stack结构电路。通过大信号仿真对CB Stack与国际上部分先进工艺下InP基的传统Stack结构电路性能进行对比，CB Stack结构在增益和峰值PAE上都比传统Stack有更好的表现。     

High gain AllnAs/GaAsSb/AllnAs NpN HBTs on InP

We report the first growth and characterization of high gain double heterojunction NpN HBTs on InP with a lattice-matched GaAs₅Sb₅ base layer. This AllnAs/GaAsSb heterojunction has almost no discontinuity in the conduction band edge, eliminating the need to grade the emitter-to-base heterojunction to achieve optimal carrier injection. The layers were grown in a solid source MBE system, using tetramer As₄ and Sb₄ sources. Be is an efficient acceptor in the GaAsSb, but the mobility is about half that measured inp type GaAs on GaAs substrates. The HBTs fabricated were large area mesa isolated transistors, with a beta of 80 at a current density of 2 kA/cm², and the gain remained high at lower current densities. The turnon voltage,V _be, is only 0.45 V at a current density of 2 A/cm².     

83GHz InP DHBT静态分频器

A static frequency divider is presented using 0.7μm lnP DHBTs with 280 GHz ft/fmax. The divider is based on ECL master-slave D-flip-flop topology with 30 HBTs and 20 resistors with a chip size 0.62 ×0.65 mm^2. The circuits use peaking inductance as a part of the loads to maximize the highest clock rate. Momentum simulation is used to accurately characterize the effect of the clock feedback lines at the W band. Test results show that the divider can operate from 1 GHz up to 83 GHz. Its phase noise is 139 dBc/Hz with 100 kHz offset. The power dissipation of divider core is 350 mW.     

GaAs1−xSbx growth by OMVPE

The system GaAs_1−xSb_x has a solid phase miscibility gap ranging from x = 0.2 to x = 0.8 at the typical growth temperature of 600 C; however, metastable alloys covering this entire composition range have been grown by organometallic vapor phase epitaxy (OMVPE) using trimethylgallium, antimony and -arsenic as the source materials. The solid composition is studied for various values of growth temperature, the ratio of Sb to total group V elements in the vapor phase and the ratio of group III to group V elements in the vapor phase. The fraction of trimethylarsenic (TMAs) pyrolyzed in the vapor phase is found to be < 1 and to vary with temperature. Taking into account the incomplete pyrolysis of TMAs, solid composition is found to be controlled by thermodynamics. The effects of temperature and vapor composition are all accurately predicted using a simple thermodynamic model assuming equilibrium to be established at the solid-vapor interface. The properties of these metastable GaAs_1−x Sb_x alloys were explored using interference contrast microscopy, room temperature and 4 K photoluminescence, Hall effect and conductivity measurements. The alloy GaAs_0.5Sb_0.5 grown lattice matched to the InP substrate has excellent surface morphology, is p-type, and the photoluminescence spectrum consists of a single, intense, fairly broad (23.5 meV half width) peak at a wavelength of 1.54 Μm.     

Ultra high-speed InP/InGaAs DHBTs with ft of 203 GHz

InP/InGaAs/InP double heterojunction bipolar transistors (DHBTs) were designed for wide band digital and analog circuits, and fabricated using a conventional mesa structure with benzocyclobutene (BCB) passivation and planarization process techniques. Our devices exhibit a maximum ft of 203 GHz, which is the highest ft for DHBTs in mainland China. The emitter size is 1.0×20 μm2. The DC current gain β is 166, and BVCEO=4.34 V. The devices reported here employ a 40 nm highly doped InGaAs base region and a 203 nm InGaAsP composite structure. They are suitable for high speed and intermediate power applications.     

SDD定义的InP DHBT大信号模型

A self-built accurate and flexible large-signal model based on an analysis of the characteristics of InP double heterojunction bipolar transistors （DHBTs） is implemented as a seven-port symbolically defined device （SDD） in Agilent ADS. The model accounts for most physical phenomena incluuing the self-heating effect, Kirk effect, soft knee effect, base collector capacitance and collector transit time. The validity and the accuracy of the large-signal model are assessed by comparing the simulation with the measurement of DC, multi-bias small signal S parameters for InP DHBTs.     

A symbolically defined InP double heterojunction bipolar transistor large-signal model

A self-built accurate and flexible large-signal model based on an analysis of the characteristics of InP double heterojunction bipolar transistors (DHBTs) is implemented as a seven-port symbolically defined device (SDD)in Agilent ADS. The model accounts for most physical phenomena incluaing the self-heating effect, Kirk effect, soft knee effect, base collector capacitance and collector transit time. The validity and the accuracy of the large-signal model are assessed by comparing the simulation with the measurement of DC, multi-bias small signal S parameters for InP DHBTs.     

最高振荡频率为325GHz的InGaAs/InP双异质结双极型晶体管

A common-base four finger InGaAs/InP double heterostructure bipolar transistor（DHBT） has been designed and fabricated using triple mesa structure and planarization technology.All processes are on 3-inch wafers. The area of each emitter finger is 1×15μm².The maximum oscillation frequency(f_max) is 325 GHz and the breakdown voltage BV_CBO is 10.6 V,which are to our knowledge both the highest f_max and BV_cbo ever reported for InGaAs/InP DHBTs in China.The high speed InGaAs/InP DHBT with a high breakdown voltage is promising for submillimeter-wave and THz electronics.     

OMVPE growth of the metastable III/V alloy GaAs0.5Sb0.5

The two crystal growth parameters most likely to affect the occurrence of GaAs_0.5Sb_0.5 spinodal decomposition during organometallic vapor phase epitaxial (OMVPE) growth, substrate temperature and substrate orientation, were investigated in detail. The temperature range studied was the widest over which good morphology layers could be grown, from 550 to 680° C. The InP substrate orientations used were (100), (221) and (311). The growth process was found to be diffusion controlled at high temperatures, but to be controlled by surface kinetics at temperatures below approximately 620° C, depending on substrate orientation. Growth of high quality layers was found to be much easier between 570 and 640° C. In addition, the 77 K PL intensity is much stronger for layers grown in this temperature range. The minimum PL halfwidth at 77 K is 20 meV and at 8 K is 16 meV. The typical room temperature hole mobilities are 100 cm²/Vs with hole concentrations of 2 x 10¹⁷ cm^-3 in undoped material. The temperature dependence of mobility is consistent with enhanced alloy scattering. Surprisingly, the growth temperature has no significant effect on either PL halfwidth or hole mobility between 560 and 660° C. The single Raman line observed for the unannealed alloy is split after annealing into two lines corresponding to the GaAs-rich and GaSb-rich alloys on either side of the range of solid immiscibility. The spinodal decomposition apparently starts at the surface where the coherency strain, which stabilizes the single phase alloy, is smallest.     

ft =203GHz的超高速InP/InGaAs双异质结晶体管

为了适应数字及模拟电路带宽的不断增加,我们在传统的台面结构基础上利用BCB钝化平坦化工艺技术,设计并研制了InP/InGaAs/InP双异质结双极型晶体管。我们研制的晶体管ft达到203GHz,是目前国内InP基DHBT的最高水平,发射极尺寸为1.0μm×20μm,电流增益β为166,击穿电压为4.34V,我们的器件采用了40nm高掺杂InGaAs基区,以及203nm含有InGaAsP复合式结构的集电区。该器件非常适合高速中功耗方面的应用。     

An InGaAs/InP 40 GHz CML static frequency divider

Static frequency dividers are widely used as a circuit performance benchmark or figure-of-merit indicator to gauge a particular device technology’s ability to implement high speed digital and integrated high performance mixed-signal circuits.We report a 2:1 static frequency divider in InGaAs/InP heterojunction bipolar transistor technology.This is the first InP based digital integrated circuit ever reported on the mainland of China. The divider is implemented in differential current mode logic(CML) with 30 transistors.The circuit operated at a peak clock frequency of 40 GHz and dissipated 650 mW from a single -5 V supply.     

GaAsSb/GaAs量子阱激光器结构的发光研究

研究了GaAsSb/GaAs应变量子阱及应变补偿量子阱激光器结构的光致发光和电注入发光.结果表明,分子束外延生长温度的改变使量子阱发光性能发生系统性变化,证明生长温度对量子阱中锑的组分和界面质量具有重要影响. 同时,低温光致发光峰的波长随激发功率密度增大发生明显蓝移,具有Ⅱ类量子阱的特点. 应变补偿量子阱激光器在波长为1.3μm附近激射,阈值电流密度约为1.8kA/cm2.     

40GHz InGaAs/InP CML 结构静态分频器

Static frequency dividers are widely used as a circuit performance benchmark or figure-of-merit indicator to gauge a particular device technology's ability to implement high speed digital and integrated high performance mixed-signal circuits.We report a 2:1 static frequency divider in InGaAs/InP heterojunction bipolar transistor technology.This is the first InP based digital integrated circuit ever reported on the mainland of China. The divider is implemented in differential current mode logic(CML) with ...