新结构微波功率SiGe HBT的数值分析

提出一种新结构的微波功率SiGe异质结双极晶体管(SiGe HBT),该结构通过在传统SiGe HBT的外基区下的集电区中挖槽并填充SiO2的方法来改善器件的高频性能.将相同尺寸的新结构和传统结构的器件仿真结果进行比较,发现新结构器件的基区-集电区电容减少了55%,因而使器件的最大有效增益提高了大约2dB,其工作在低压(Vce=4.5V)和高压(Vce=28V)情况下的最高振荡频率分别提高了24%和10%.     

基于1.5 μm BiCMOS 工艺的SiGe HBT器件设计优化

基于非选择性外延,自对准注入技术,集电区选择性注入和快速热退火工艺,提出了一种适用于1.5μm BiCMOS集成技术的SiGe HBT器件结构。该结构具有内基区薄,外基区厚,B/E结两侧杂质浓度低,发射极/基极自对准诸优点。利用TSuprem4和Medici进行工艺模拟和电学特性仿真。结果表明,所设计的的SiGe HBT具有良好的电学特性,其最大电流增益为210,当Vce=2.5 V时,截止频率达到65 GHz,验证了器件结构设计的合理性。     

高性能锗硅异质结器件击穿特性的研究

对高频下的SiGe HBT器件击穿特性进行了研究。借助TCAD仿真工具,分析了影响器件击穿特性的基区Ge分布与集电区掺杂浓度超结结构。在3种不同Ge分布下,仿真结果表明,基区Ge的均匀分布有利于提高击穿电压;同时将超结结构引入集电区后,SiGe HBT器件的击穿电压提高了36%,由2.5 V提高到3.4 V。     

超高压SiGe HBT器件结构及制作工艺研究

介绍了一种超高压锗硅异质结双极晶体管(SiGe HBT)的器件结构及制作工艺。该器件增大了N型赝埋层到有源区的距离,采用厚帽层锗硅基区及低浓度发射区的制作工艺,以提高SiGe HBT的击穿电压;在基区和发射区之间利用快速热处理提高工艺稳定性,并使HBT的电流增益(β)恢复到原来水平,以弥补厚帽层锗硅基区及低发射区浓度造成的电流增益降低。基区断开时,发射区到集电区的击穿电压(BVCEO)提高至10V,晶体管特征频率达到20GHz。     

非外延集电区的超高压锗硅异质结双极晶体管

介绍了在0.18 μm逻辑工艺平台上全新设计的超高压锗硅异质结双极晶体管(SiGe HBT),该器件改变了外延的一维纵向集电区,而采用了通过离子注入掺杂的“L形”二维集电区结构,集电区包括本征基区下方的纵向集电区和场氧底部横向集电区.该器件可在同一工艺中通过版图中横向集电区长度的变化实现不同的击穿电压,因此可制作超高压...     

SBFL结构SiGe HBT器件的击穿特性研究

对高频SiGe HBT器件的击穿特性进行了研究。借助TCAD仿真工具,对超结结构引入器件集电区后的击穿特性进行了分析,提出了一种采用分裂浮空埋层结构(SBFL)的SiGe异质结器件。这种结构改善了器件的内部电场分布,电场分布由原来的单三角形分布变成双三角形分布。仿真结果表明,该器件结构的击穿电压由原有的3.6 V提高到5.4 V,提高了50%。     

SiGe HBT基区结构的优化对欧拉电压的影响

欧拉电压是SiGe HBT一项重要的直流参数,受到基区结构(如Ge组分)的影响。研究发现,高温过程会导致硼的外扩散,从而影响异质结的位置,使欧拉电压受到影响。实验发现,通过优化基区结构,加厚CB结处i-SiGe厚度,可获得VA=520 V,βVA=164,320 V的SiGe HBT。     

SiGe异质结双极晶体管的基区优化

对应用于高频微波功率放大器的SiGe异质结双极晶体管(HBT)的基区进行了优化.研究发现,器件对基区Ge组分以及掺杂浓度十分敏感.采用重掺杂基区,适当提高Ge组分并形成合适的浓度分布,可以有效地改进SiGe HBT的直流特性,同时能够提高器件的特征频率.晶体管主要性能的提高使SiGe HBT技术在微波射频等高频电子领域得到更加广泛的应用.     

新型恒压控制型负阻HBT的研制进展

研究了HBT产生负阻的可能机制,通过对材料结构和器件结构的特殊设计,采用常规台面HBT工艺,先后研制出3类高电流峰谷比的恒压控制型负阻HBT.超薄基区HBT的负阻特性是由超薄基区串联电阻压降调制效应造成的,在GaAs基InGaP/GaAs和AlGaAs/GaAs体系DHBT中均得到了验证.双基区和电阻栅型负阻HBT均为复合型负阻器件.双基区负阻HBT通过刻断基区,电阻栅负阻HBT通过在集电区制作基极金属形成集电区反型层,构成纵向npn与横向pnp的复合结构,由反馈结构(pnp)的集电极电流来控制主结构(npn)的基极电流从而产生负阻特性.3类负阻HBT与常规HBT在结构和工艺上兼容,兼具HBT的高速高频特性和负阻器件的双稳、自锁、节省器件的优点.     

全部耗尽SOI SiGe HBT集电结渡越时间模型研究

研究了与CMOS兼容的SOI SiGe HBT结构。首先,分析了SOI SiGe HBT与传统SiGe HBT在结构上的不同之处。然后,针对新结构的全部耗尽工作模式,建立了考虑电流效应的集电结渡越时间模型。最后,讨论了渡越时间与集电区掺杂浓度、集电结电压、传输电流的关系,并与传统器件的渡越时间进行了比较。该渡越时间模型的建立为SOI SiGe HBT特征频率的设计与优化提供了理论基础。     

TiSi2在微波低噪声SiGe HBT中的应用

通过在SiGe HBT外基区和多晶发射极上制作TiSi2,从而使器件的高频噪声系数得到进一步降低.以PD=200mW的SiGe HBT为例,采用TiSi2工艺的噪声系数典型值为F=1.6dB@1.1GHz,明显低于无TiSi2工艺SiGe HBT的2.0dB@1.1GHz,且频率越高,二者差别越大.     

SiGe HBT and BiCMOS technologies for optical transmission and wireless communication systems

Technologies for a self-aligned SiGe heterojunction bipolar transistor (HBT) and SiGe HBTs with CMOS transistors (SiGe BiCMOS) have been developed for use in optical transmission and wireless communication systems. n-Si cap/SiGe-base multilayer fabricated by selective epitaxial growth (SEG) was used to obtain both high-speed and low-power performance for the SiGe HBTs. The process except the SEG is almost completely compatible with well-established Si bipolar-CMOS technology, and the SiGe HBT and BiCMOS were fabricated on a 200-mm wafer line. High-quality passive elements, i.e., high-precision poly-Si resistors, a high-Q varactor, an MIM capacitor, and high-Q spiral inductors have also been developed to meet the demand for integration of the sophisticated functions. A cutoff frequency of 130 GHz, a maximum oscillation frequency of 180 GHz, and an ECL gate-delay time of 5.3 ps have been demonstrated for the SiGe HBTs. An IC chipset for 40-Gb/s optical-fiber links, a single-chip 10-Gb/s transceiver large-scale IC (LSI), a 5.8-GHz electronic toll collection transceiver IC, and other practical circuits have been implemented by applying the SiGe HBT or BiCMOS technique.     

An 18-GHz 300-mW SiGe power HBT

An 18-GHz, 300-mW SiGe power heterojunction bipolar transistor (HBT) is demonstrated. The optimization of SiGe HBT vertical profile has enabled this type of devices to operate with high gain and high power at this high frequency. In the common-base configuration, a continuous wave output power of 24.73 dBm with a power gain of 4.5 dB was measured from a single 20-emitter stripe SiGe (2/spl times/30 /spl mu/m/sup 2/ of each emitter finger) double HBT. The overall performance characteristics represent the state-of-the-art SiGe power HBTs operating in the K-band frequency range.     

The influence of Ge grading on the bias and temperaturecharacteristics of SiGe HBTs for precision analog circuits

This paper analyzes the effects of Ge profile shape on the bias and temperature characteristics of advanced UHV/CVD SiGe heterojunction bipolar transistors (HBTs). The widely used bandgap reference (BGR) design equation and a more general analytical expression incorporating Ge grading developed in this work are used to compare silicon devices to their SiGe counterparts. Theory, device measurements, and SPICE simulations are used to investigate the impact of Ge grading on SiGe HBT precision voltage references. It is concluded that conventional SPICE can be used to account for Ge grading effects in SiGe HBT modeling. Sufficient Ge grading can have a significant impact on the accuracy of precision voltage references, particularly at reduced temperatures, and thus warrants attention     

500 GHz cutoff frequency SiGe HBTs

A current gain cutoff frequency f_T of 508 GHz is reported for a SiGe heterojunction bipolar transistor (HBT) operating at 40 K. This 63% increase over the 311 GHz value measured at room temperature results from the overall decrease of the transit and charging times. Two HBTs are compared to highlight the importance of the topology of the HBT to reach maximum performances.     

SiGe HBT低频噪声PSPICE模拟分析

对SiGe HBT低频噪声的各噪声源进行了较全面的分析,据此建立了SPICE噪声等效电路模型,进一步用PSPICE软件对SiGe HBT的低频噪声特性进行了仿真模拟.研究了频率、基极电阻、工作电流和温度等因素对低频噪声的影响.模拟结果表明,相较于Si BJT和GaAs HBT,SiGe HBT具有更好的低频噪声特性;在低频范围内,可通过减小基极电阻、减小工作电流密度或减小发射极面积、降低器件的工作温度等措施来有效改善SiGe HBT的低频噪声特性.所得结果对SiGe HBT的设计和应用有重要意义.     

Improvement on Frequency Performance of SOI SiGe HBT

Based on the advantages of SOI technology, the frequency performance of SiGe HBT with SOI structure has been simulated. Compared with bulk SiGe HBT, the results show that the buried oxide layer （BOX） can reduce collector-base capacitance CCB with the maximum value 89.3%, substrate-base capacitance CSB with 94. 6%, and the maximum oscillation frequency is improved by 2.7. The SOl structure improves the frequency performance of SiGe HBT, which is adaptable to high-speed and high power applications.     

SiGe HBT的脉冲中子及γ辐射效应

测量了反应堆脉冲中子及γ辐照SiGe HBT典型电参数变化.在反应堆1×1013cm-2的脉冲中子注量和256.85Gy(Si)γ总剂量辐照后,SiGe HBT静态共射极直流增益减小了20%.辐照后基极电流、结漏电流增大,集电极电流、击穿电压减小.特征截止频率fT基本不变,fmax略有减小.初步分析了SiGe HBT反应堆脉冲中子及γ辐射的损伤机理.     

Modeling and characterization of SiGe HBT low-frequency noise figures-of-merit for RFIC applications

We present the first systematic experimental and modeling results of noise corner frequency (f/sub C/) and noise corner frequency to cutoff frequency ratio (f/sub C//f/sub T/) for SiGe heterojunction bipolar transistors (HBTs) in a commercial SiGe RF technology. The f/sub C/ and f/sub C//f/sub T/ ratio are investigated as a function of operating collector current density, SiGe profile, breakdown voltage, and transistor geometry. We demonstrate that both the f/sub C/ and f/sub C//f/sub T/ ratio can be significantly reduced by careful SiGe profile optimization. A comparison of the f/sub C/ and f/sub C//f/sub T/ ratio for high breakdown and standard breakdown voltage devices is made. Geometrical scaling data show that the SiGe HBT with A/sub E/=0.5/spl times/2.5 /spl mu/m/sup 2/ has the lowest f/sub C/ and f/sub C//f/sub T/ ratio compared to other device geometries. An f/sub C/ reduction of nearly 50% can be achieved by choosing this device as the unit cell in RF integrated-circuit design.