A self aligned InGaP/GaAs power HBTs for L band power amplifier with low bias voltage are described.Base emitter metal self aligning,air bridge,and wafer thinning are used to improve microwave power performance.A...A self aligned InGaP/GaAs power HBTs for L band power amplifier with low bias voltage are described.Base emitter metal self aligning,air bridge,and wafer thinning are used to improve microwave power performance.A power HBT with double size of emitter of (3μm×15μm)×12 is fabricated.When the packaged HBT operates in class AB at a collector bias of 3V,a maximum 23dBm output power with 45% power added efficiency is achieved at 2GHz.The results show that the InGaP/GaAs power HBTs have great potential in mobile communication systems operating at low bias voltage.展开更多
PolYimide passivation and planarization process techniques for high speed InP/InGaAs single heterojunction bipolar transistors （SHBTS） are developed. A maximum extrapolated ft of 210GHz is achieved for the SHBT with...PolYimide passivation and planarization process techniques for high speed InP/InGaAs single heterojunction bipolar transistors （SHBTS） are developed. A maximum extrapolated ft of 210GHz is achieved for the SHBT with 1.4μm × 15μm emitter area at VCE = 1. 1V and Ic = 33.5mA. This device is suitable for high speed and low power applications,such as ultra high speed mixed signal circuits and optoelectronic communication ICs.展开更多
Based on the thermal network of the two-dimensional heterojunction bipolar transistors(HBTs) array, the thermal resistance matrix is presented, including the self-heating thermal resistance and thermal coupling resist...Based on the thermal network of the two-dimensional heterojunction bipolar transistors(HBTs) array, the thermal resistance matrix is presented, including the self-heating thermal resistance and thermal coupling resistance to describe the self-heating and thermal coupling effects, respectively.For HBT cells along the emitter length direction, the thermal coupling resistance is far smaller than the self-heating thermal resistance, and the peak junction temperature is mainly determined by the self-heating thermal resistance.However, the thermal coupling resistance is in the same order with the self-heating thermal resistance for HBT cells along the emitter width direction.Furthermore, the dependence of the thermal resistance matrix on cell spacing along the emitter length direction and cell spacing along the emitter width direction is also investigated, respectively.It is shown that the moderate increase of cell spacings along the emitter length direction and the emitter width direction could effectively lower the self-heating thermal resistance and thermal coupling resistance,and hence the peak junction temperature is decreased, which sheds light on adopting a two-dimensional non-uniform cell spacing layout to improve the uneven temperature distribution.By taking a 2 × 6 HBTs array for example, a twodimensional non-uniform cell spacing layout is designed, which can effectively lower the peak junction temperature and reduce the non-uniformity of the dissipated power.For the HBTs array with optimized layout, the high power-handling capability and thermal dissipation capability are kept when the bias voltage increases.展开更多
A transimpedance amplifier based on InGaP/GaAs HBTs,which is applicable for 10Gbps bit rate,is developed and realized.Compact chip layout guarantees good flat gain,linear phase,and small group delay time variation.Mea...A transimpedance amplifier based on InGaP/GaAs HBTs,which is applicable for 10Gbps bit rate,is developed and realized.Compact chip layout guarantees good flat gain,linear phase,and small group delay time variation.Measured transimpedance gain is 40 dB·Ω and 3dB bandwidth is 10GHz.展开更多
The structure and microwave characteristics of low-voltage SiGe power HBTs are given.With this structure,the device can operate in a low-voltage and high-current state.By using an interdigital emitter strip layout and...The structure and microwave characteristics of low-voltage SiGe power HBTs are given.With this structure,the device can operate in a low-voltage and high-current state.By using an interdigital emitter strip layout and the operating voltage ranging from 3 to 4V,the output power in Class C operation can reach 1 65W at 1GHz,with the gain of 8dB.The highest collector efficiency is 67 8% under 3V.展开更多
The performance of low frequency noise(LFN)in SiGe heterojunction bipolar transistors(HBTs)is presented.The experimental results indicate that the performance of LFN in SiGe HBTs agrees with classical LFN theory.Based...The performance of low frequency noise(LFN)in SiGe heterojunction bipolar transistors(HBTs)is presented.The experimental results indicate that the performance of LFN in SiGe HBTs agrees with classical LFN theory.Based on classical LFN theory,the source of LFN in SiGe HBTs is confirmed from Hooge modal and McWhorter model simultaneously.Furthermore,according to this results,the base current coefficient α is extracted and the relationship between current noise power spectral density and base current is also shown.展开更多
The influence of a heterojunction in the vicinity of a graded BC junction on the performance of npn SiGe HBTs is studied. SiGe HBTs differing only in heterojunction position in the vicinity of a graded BC junction are...The influence of a heterojunction in the vicinity of a graded BC junction on the performance of npn SiGe HBTs is studied. SiGe HBTs differing only in heterojunction position in the vicinity of a graded BC junction are simulated by means of 2D Medici software for DC current gain and frequency characteristics. In addition, the simulated DC current gains and cut-off frequencies are compared at different collector-emitter bias voltages. Through the simulation results, both DC and HF device performance are found to be strongly impacted by degree of confinement of the neutral base in the SiGe layer, even in the absence of a conduction band barrier. This conclusion is of significance for designing and analyzing SiGe HBTs.展开更多
In this paper we investigate two techniques for single event effect(SEE) mitigation by using back junction and p^+buffer layer in non-deep trench isolation(DTI) domestic silicon–germanium heterojunction bipolar trans...In this paper we investigate two techniques for single event effect(SEE) mitigation by using back junction and p^+buffer layer in non-deep trench isolation(DTI) domestic silicon–germanium heterojunction bipolar transistors(SiGe HBTs)based on technology computer aided design(TCAD) simulation. The effectiveness of the two mitigation techniques and the influence of various structure parameters are investigated. Simulation results indicate that the two techniques are more effective in reducing collector charge collection induced by heavy ions striking at positions outside the collector–substrate(C–S) junction where charge collection is dominated by diffusion. By properly adjusting the parameters, charge collection of events outside the C–S junction can be reduced by more than an order of magnitude, while charge collection of events in the device center is halved without affecting the direct current(DC) and alternating current(AC) characteristics of the SiGe HBTs.展开更多
The effect of lateral structure parameters of transistors including emitter width, emitter length, and emitter stripe number on the performance parameters of the active inductor （AI）, such as the effective inductanc...The effect of lateral structure parameters of transistors including emitter width, emitter length, and emitter stripe number on the performance parameters of the active inductor （AI）, such as the effective inductance Ls, quality factor Q, and self-resonant frequency too is analyzed based on 0.35%tm SiGe BiCMOS process. The simulation results show that for AI operated under fixed current density Jc, the HBT lateral structure parameters have significant effect on Ls but little influence on Q and 090, and the larger Ls can be realized by the narrow, short emitter stripe and few emitter stripes of SiGe HBTs. On the other hand, for AI with fixed HBT size, smaller Jc is beneficial for AI to obtain larger Ls, but with a cost of smaller Q and 090. In addition, under the fixed collector current Ic, the larger the size of HBT is, the larger Ls becomes, but the smaller Q and ab become. The obtained results provide a reference for selecting geometry of transistors and operational condition in the design of active inductors.展开更多
Heterojunction Bipolar Transistors with SiGe base and Si emitter and collector have increasingly become important in high speed applications in electronics due to better performance of these devices with a modest incr...Heterojunction Bipolar Transistors with SiGe base and Si emitter and collector have increasingly become important in high speed applications in electronics due to better performance of these devices with a modest increase in complexity of fabrication process. Speed of these devices is mainly determined by transit time of minority carriers across the device. Base transit time is the most important component of the total transit time. An analytical model is developed here to predict the variation of base transit time with Ge content, base doping concentration, temperature, and other device parameters. Studies have been made for both uniform and exponential doping distributions with different Ge profiles in the base region. Band gap narrowing effect due to high doping concentration is also taken into account in the model.展开更多
In this paper, we present an improved high-frequency equivalent circuit for SiGe heterojunction bipolar transistors（HBTs） with a CBE layout, where we consider the distributed effects along the base region. The actua...In this paper, we present an improved high-frequency equivalent circuit for SiGe heterojunction bipolar transistors（HBTs） with a CBE layout, where we consider the distributed effects along the base region. The actual device structure is divided into three parts： a link base region under a spacer oxide, an intrinsic transistor region under the emitter window,and an extrinsic base region. Each region is considered as a two-port network, and is composed of a distributed resistance and capacitance. We solve the admittance parameters by solving the transmission-line equation. Then, we obtain the smallsignal equivalent circuit depending on the reasonable approximations. Unlike previous compact models, in our proposed model, we introduce an additional internal base node, and the intrinsic base resistance is shifted into this internal base node,which can theoretically explain the anomalous change in the intrinsic bias-dependent collector resistance in the conventional compact model.展开更多
Heavy doping of the base in HBTs brings about a bandgap narrowing （BGN） effect, which modifies the intrinsic carrier density and disturbs the band offset, and thus leads to the change of the currents. Based on a the...Heavy doping of the base in HBTs brings about a bandgap narrowing （BGN） effect, which modifies the intrinsic carrier density and disturbs the band offset, and thus leads to the change of the currents. Based on a thermionic-field-diffusion model that is used to the analyze the performance of an abrupt HBT with a heavydoped base, the conclusion is made that, although the BGN effect makes the currents obviously change due to the modification of the intrinsic carrier density, the band offsets disturbed by the BGN effect should also be taken into account in the analysis of the electrical characteristics of abrupt HBTs. In addition, the BGN effect changes the bias voltage for the onset of Kirk effects.展开更多
文摘A self aligned InGaP/GaAs power HBTs for L band power amplifier with low bias voltage are described.Base emitter metal self aligning,air bridge,and wafer thinning are used to improve microwave power performance.A power HBT with double size of emitter of (3μm×15μm)×12 is fabricated.When the packaged HBT operates in class AB at a collector bias of 3V,a maximum 23dBm output power with 45% power added efficiency is achieved at 2GHz.The results show that the InGaP/GaAs power HBTs have great potential in mobile communication systems operating at low bias voltage.
文摘PolYimide passivation and planarization process techniques for high speed InP/InGaAs single heterojunction bipolar transistors （SHBTS） are developed. A maximum extrapolated ft of 210GHz is achieved for the SHBT with 1.4μm × 15μm emitter area at VCE = 1. 1V and Ic = 33.5mA. This device is suitable for high speed and low power applications,such as ultra high speed mixed signal circuits and optoelectronic communication ICs.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61006059 and 61774012)Beijing Municipal Natural Science Foundation,China(Grant No.4143059)+3 种基金Beijing Municipal Education Committee,China(Grant No.KM201710005027)Postdoctoral Science Foundation of Beijing,China(Grant No.2015ZZ-11)China Postdoctoral Science Foundation(Grant No.2015M580951)Scientific Research Foundation Project of Beijing Future Chip Technology Innovation Center,China(Grant No.KYJJ2016008)
文摘Based on the thermal network of the two-dimensional heterojunction bipolar transistors(HBTs) array, the thermal resistance matrix is presented, including the self-heating thermal resistance and thermal coupling resistance to describe the self-heating and thermal coupling effects, respectively.For HBT cells along the emitter length direction, the thermal coupling resistance is far smaller than the self-heating thermal resistance, and the peak junction temperature is mainly determined by the self-heating thermal resistance.However, the thermal coupling resistance is in the same order with the self-heating thermal resistance for HBT cells along the emitter width direction.Furthermore, the dependence of the thermal resistance matrix on cell spacing along the emitter length direction and cell spacing along the emitter width direction is also investigated, respectively.It is shown that the moderate increase of cell spacings along the emitter length direction and the emitter width direction could effectively lower the self-heating thermal resistance and thermal coupling resistance,and hence the peak junction temperature is decreased, which sheds light on adopting a two-dimensional non-uniform cell spacing layout to improve the uneven temperature distribution.By taking a 2 × 6 HBTs array for example, a twodimensional non-uniform cell spacing layout is designed, which can effectively lower the peak junction temperature and reduce the non-uniformity of the dissipated power.For the HBTs array with optimized layout, the high power-handling capability and thermal dissipation capability are kept when the bias voltage increases.
文摘A transimpedance amplifier based on InGaP/GaAs HBTs,which is applicable for 10Gbps bit rate,is developed and realized.Compact chip layout guarantees good flat gain,linear phase,and small group delay time variation.Measured transimpedance gain is 40 dB·Ω and 3dB bandwidth is 10GHz.
文摘The structure and microwave characteristics of low-voltage SiGe power HBTs are given.With this structure,the device can operate in a low-voltage and high-current state.By using an interdigital emitter strip layout and the operating voltage ranging from 3 to 4V,the output power in Class C operation can reach 1 65W at 1GHz,with the gain of 8dB.The highest collector efficiency is 67 8% under 3V.
基金National Natural Science Foundation of China (60776051 and 60376033)Beijing Municipal Natural Science Foun-dation,China (4082007)+4 种基金State 973 project, Beijing Municipal Education Committee,China (KM200710005015)Beijing Municipaltrans -century Talent Project (67002013200301)Young Science Foundation of BJUT (97002013200701)Ph.D Start Science Foundation of BJUT(52002013200701)the 6th Science and Technology Postgraduate Foundation of BJUT(ykj -2007-1970)
文摘The performance of low frequency noise(LFN)in SiGe heterojunction bipolar transistors(HBTs)is presented.The experimental results indicate that the performance of LFN in SiGe HBTs agrees with classical LFN theory.Based on classical LFN theory,the source of LFN in SiGe HBTs is confirmed from Hooge modal and McWhorter model simultaneously.Furthermore,according to this results,the base current coefficient α is extracted and the relationship between current noise power spectral density and base current is also shown.
文摘The influence of a heterojunction in the vicinity of a graded BC junction on the performance of npn SiGe HBTs is studied. SiGe HBTs differing only in heterojunction position in the vicinity of a graded BC junction are simulated by means of 2D Medici software for DC current gain and frequency characteristics. In addition, the simulated DC current gains and cut-off frequencies are compared at different collector-emitter bias voltages. Through the simulation results, both DC and HF device performance are found to be strongly impacted by degree of confinement of the neutral base in the SiGe layer, even in the absence of a conduction band barrier. This conclusion is of significance for designing and analyzing SiGe HBTs.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11775167,11575138,and 11835006)
文摘In this paper we investigate two techniques for single event effect(SEE) mitigation by using back junction and p^+buffer layer in non-deep trench isolation(DTI) domestic silicon–germanium heterojunction bipolar transistors(SiGe HBTs)based on technology computer aided design(TCAD) simulation. The effectiveness of the two mitigation techniques and the influence of various structure parameters are investigated. Simulation results indicate that the two techniques are more effective in reducing collector charge collection induced by heavy ions striking at positions outside the collector–substrate(C–S) junction where charge collection is dominated by diffusion. By properly adjusting the parameters, charge collection of events outside the C–S junction can be reduced by more than an order of magnitude, while charge collection of events in the device center is halved without affecting the direct current(DC) and alternating current(AC) characteristics of the SiGe HBTs.
基金Project supported by the Natural Science Foundation of BeijingChina(Grant Nos.4142007 and 4122014)+1 种基金the National Natural Science Foundation of China(Grant No.61574010)the Higher Educational Science and Technology Program of Shandong Province,China(Grant No.J13LN09)
文摘The effect of lateral structure parameters of transistors including emitter width, emitter length, and emitter stripe number on the performance parameters of the active inductor （AI）, such as the effective inductance Ls, quality factor Q, and self-resonant frequency too is analyzed based on 0.35%tm SiGe BiCMOS process. The simulation results show that for AI operated under fixed current density Jc, the HBT lateral structure parameters have significant effect on Ls but little influence on Q and 090, and the larger Ls can be realized by the narrow, short emitter stripe and few emitter stripes of SiGe HBTs. On the other hand, for AI with fixed HBT size, smaller Jc is beneficial for AI to obtain larger Ls, but with a cost of smaller Q and 090. In addition, under the fixed collector current Ic, the larger the size of HBT is, the larger Ls becomes, but the smaller Q and ab become. The obtained results provide a reference for selecting geometry of transistors and operational condition in the design of active inductors.
文摘Heterojunction Bipolar Transistors with SiGe base and Si emitter and collector have increasingly become important in high speed applications in electronics due to better performance of these devices with a modest increase in complexity of fabrication process. Speed of these devices is mainly determined by transit time of minority carriers across the device. Base transit time is the most important component of the total transit time. An analytical model is developed here to predict the variation of base transit time with Ge content, base doping concentration, temperature, and other device parameters. Studies have been made for both uniform and exponential doping distributions with different Ge profiles in the base region. Band gap narrowing effect due to high doping concentration is also taken into account in the model.
基金Project supported by the National Natural Science Funds of China(Grant Nos.61574056 and 61504156)the Natural Science Foundation of Shanghai,China(Grant No.14ZR1412000)+1 种基金Shanghai Sailing Program,China(Grant No.17YF1404700)the Science and Technology Commission of Shanghai Municipality,China(Grant No.14DZ2260800)
文摘In this paper, we present an improved high-frequency equivalent circuit for SiGe heterojunction bipolar transistors（HBTs） with a CBE layout, where we consider the distributed effects along the base region. The actual device structure is divided into three parts： a link base region under a spacer oxide, an intrinsic transistor region under the emitter window,and an extrinsic base region. Each region is considered as a two-port network, and is composed of a distributed resistance and capacitance. We solve the admittance parameters by solving the transmission-line equation. Then, we obtain the smallsignal equivalent circuit depending on the reasonable approximations. Unlike previous compact models, in our proposed model, we introduce an additional internal base node, and the intrinsic base resistance is shifted into this internal base node,which can theoretically explain the anomalous change in the intrinsic bias-dependent collector resistance in the conventional compact model.
基金supported by the State Key Development Program for Basic Research of China (No. 2003CB314901)
文摘Heavy doping of the base in HBTs brings about a bandgap narrowing （BGN） effect, which modifies the intrinsic carrier density and disturbs the band offset, and thus leads to the change of the currents. Based on a thermionic-field-diffusion model that is used to the analyze the performance of an abrupt HBT with a heavydoped base, the conclusion is made that, although the BGN effect makes the currents obviously change due to the modification of the intrinsic carrier density, the band offsets disturbed by the BGN effect should also be taken into account in the analysis of the electrical characteristics of abrupt HBTs. In addition, the BGN effect changes the bias voltage for the onset of Kirk effects.
