Study OF Ultra-High Speed Heterojunction Bipolar Transistors with a Heavily Carbon-Doped Base

重碳掺杂基极超高速异质结双极晶体管的研究

基本信息

批准号：
04555066
负责人：
KONAGAI Makoto
金额：
$ 11.65万
依托单位：
Tokyo Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research (B)
财政年份：
1992
资助国家：
日本
起止时间：
1992 至 1994
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-04555066/
关键词：
MOMBE Carbon Carbon-doped baes HBT Heavy doping InGaP Tertiarybutylphosphine GaAs HBT InP InGaAs HBT 超高濃度ドーピング GaAs InGaAs ターシャリブチルフォスフィン HBT トリメチルガリウムネオペンタン

项目摘要

Heterojunction bipolar transistors (HBTs) have attracted much attention as high-speed devices. In this research, it was strongly proposed that for further improved device performance of HBTs, reduction of base resistance is greatly important. In other words, heavily doped base layr with the well-confined base dopant is one of key structural parameters for realizing high-speed HBTs.From these points, effects of reduced base resistance on static and dynamic characteristics of InGaP/GaAs HBTs with an ultra-high doped base were studied by solving the basic device equations and the hybrid-pi type equivalent circuit model. By increasing the base hole concentration to 1.5x10^<21>cm^<-3>, current gains were estimated to be over 10 by assuming the minority carrier lifetime gamma_n of 10-100ps, and current-gain cutoff frequency f_T of 110 GHz and maximum oscillation frequency f_<max> of 160 GHz were predicted. Switching characteristics were also studied by using a SPICE simulator, and propagatio … More n delay time t_<pd> of l ps/gate was achieved in that device structures.Based on this consideration, heavy impurity-doping technique is developed by using novel crystal growth technique : metalorganic molecular beam epitaxy (MOMBE) . Instead of conventional p-type dopants such as beryllium (Be) and zinc (Zn) for base layr in HBTs, carbon (C) is proposed as a novel base dopant because of excellent stability and capability of heavy doping. Heavily carbon-doped p-type GaAs and InGaAs were developed as base materials by MOMBE with trimethylgallium (TMG) , and carbon-doping characteristics and electrical, optical and structural properties were studied in detail. Furthermore, phosphide materials such as InGaP and InP are also proposed in this research as novel emitter materials of the HBTs because of the tendency of low surface recombination velocity, and MOMBE growth of these compounds is investigated with new metalorganic phosphorus precursor : tertiarybutylphosphine (TBP) .In the growth of high quality materials, the catalysis by means of heated tantalum (Ta) inside the cracking cell was important to effectively decompose the TBP as compared to simple pyrolysis. Controllability of Si-doping in In_<0.5>Ga_<0.5>P suitable for HBT application was also studied by using cracked Si_2H_6. In the growth of InP by MOMBE with TBP,it was revealed that carbon from the TBP is incorporated and acts as well-activated donor.By combining these MOMBE growth techniques, InP/InGaAs HBTs with carbon-doped n-type InP emitter and carbon-doped p-type InGaAs base are proposed and fabricated for the first time in the world. In common-emitter static characteristics, relatively large commonemitter breakdown voltage BV_<CEO>above 6 V was achieved, and small signal current gain h_<fe> of 20 and d.c.current gain h_<FE> of 11 were obtained at collector current density J_C of 0.15kA/cm^2 for a device with emitter area A_E of 80*80mum^2.Furthermore, InGaP/GaAs HBTs having an ultrahigh carbon-doped base with a hole concentration of the order of 10^<21>cm^<-3> are realized for the first time. By using that device structure, improved high-frequency performance is strongly expected because base resistance could be extremely decreased due to the ultra-high doping in the base. In fact, h_<fe> of 16 and h_<FE> of 12 were obtained for devices with a base thickness of 15 nm. In the reliability measurements, a significant degradation of current gain was not observed in the range investigated, indicating a perfect stability of carbon as a p-type dopant. In conclusions, successful realization of HBTs with unique original structures ; Inp/InGaAs HBTs with carbon-doped InP emitter and carbondoped InGaAs base and InGap/GaAs HBTs with an ultra-high carbon-doped base (p=1.5*10^<21>cm^<-3>) , was studied for the first time. Less

异射线两极发射器（HBT）吸引了作为高速设备的广泛关注。在这项研究中，强烈建议，为了进一步提高HBT的设备性能，降低基本电阻非常重要。换句话说，具有良好的基础掺杂剂是实现高速HBT的关键结构参数之一。从这些要点，通过求解基本设备等电期，通过求解了超高掺杂基础的Ingap/Gaas HBT的静态和动态特征的降低对基础/GAAS HBT的静态和动态特征的降低对静态和动态特征的影响。通过将基本孔浓度提高到1.5x10^<21> cm^<-3>，通过假设少数载流子寿命gamma_n为10-100ps，电流的增长估计超过10，而电流增益的截止频率为110 GHz和最大振荡频率f_ax> 160 GHz的最大振荡频率f_ max>。开关特性还通过使用香料模拟器进行了研究，并在该设备结构中实现了L ps/gote的延迟时间t_ <pd>更多的pasgaTio。基于此考虑，通过使用新颖的晶体生长技术开发了重型杂质兴奋剂技术：金属有机分子束束（MOMBER（MOMBE））。碳（c）不是传统的p型掺杂剂，例如贝莱群（BE）和锌（Zn），而是由于浓度的出色稳定性和能力，因此提出了碳（C）作为一种新型的基础掺杂剂。用三甲基甲基（TMG）的MOMBE开发了大量碳掺杂的P-type GAA和INGAA，并详细研究了碳掺杂特性以及电气，光学和结构特性。 Furthermore, phosphide materials such as InGaP and InP are also proposed in this research as novel emitter materials of the HBTs because of the tendency of low surface recombination velocity, and MOMBE growth of these compounds is investigated with new metalorganic phosphorus precursor: tertiarybutylphosphine (TBP) .In the growth of high quality materials, the catalyst by means of heated tantalum (Ta) inside the与简单的热解相比，开裂细胞对于有效分解TBP很重要。还使用破裂的SI_2H_6研究了适合HBT应用的IN_ <0.5> Ga_ <0.5> P中Si掺杂的可控性。在MOMBE与TBP的INP增长中，据透露，来自TBP的碳被合并并作为充分激活的供体。通过将这些MOMBE增长技术相结合，INP/INGAAS HBT与碳掺杂的N型N型N型INP INP INP和碳竞争P-type的P-type IngaAS基础是拟议的，并且是Frimed fragity和Frunce in Yearking in World in World in World inthe World in the World。在公共发射极的静态特征中，达到了6 V上方的相对大型公共发射器崩溃电压bv_ <ceo>，并且在收集器电流密度为0.15ka/cm^2的收集器电流密度j_c/cm^2的设备中，获得了11个h_e a_e/gay的设备，并获得了少量信号电流增益H_ <fe>，h_ <efe> 11获得了11个*80*80mers a__e a _ _ 80*fur的设备。首次实现具有10^<21> cm^<-3>孔浓度的超高碳掺杂底座。通过使用该设备结构，高频性能得到了强烈的预期，因为由于底座中的超高掺杂，基本电阻可能会极大地降低。实际上，对于基本厚度为15 nm的设备，获得了16和h_ <fe> 12的H_ <fe>。在可靠性测量值中，在研究范围内未观察到当前增益的显着降解，表明碳作为P型掺杂剂的完美稳定性。总而言之，成功实现具有独特原始结构的HBT； INP/INGAAS HBTS具有碳掺杂的INP发射极和碳掺杂的INGAAS底座和具有超高碳掺杂底座的INGAP/GAAS HBT（P = 1.5*10^<21> cm^<-3>），首次研究了。较少的