High breakdown voltage 4H-SiC MESFETs with floating metal strips

A high breakdown voltage 4H-SiC MESFET with floating metal strips (FMS) was proposed. The maximum electrical field of the MESFET gate is clamped after surface depletion layer punch through to FMS. The optimized results showed that the breakdown voltage of the 4H-SiC MESFET with two strips and one strip are 180% and 95% larger than that of the conventional one without FMS and meanwhile maintain almost same saturation drain current. The maximum theoretical output power density of the 4H-SiC MESFET with two strips and one strip are 14.5 W and 10.0 W compared to 4.8 W of the conventional structure. The cut-off frequency (f_T) of 14.7 GHz and 15.6 GHz and the maximum oscillation frequency (f_max) of 44.8 GHz and 48.7 GHz for the 4H-SiC MESFET with two strips and one strip are obtained respectively, which is just a little bit lower than that of the conventional structure.     

A new analytical model for photo-dependent capacitances of GaAs MESFET’s with emphasis on the substrate related effects

A new analytical model for optical and bias dependent nonlinear capacitances of GaAs MESFET which is valid for both linear and saturation regions has been proposed in this paper. The novelty lies in modeling of internal and external photovoltaic effects that includes deep level traps in the substrate and surface recombination at metal–semiconductor interface of the gate. The effect of high field domain formation at the drain end in the saturation region has also been included to improve the accuracy of the present model. The model presents backgating effects on gate–source and gate–drain capacitances of GaAs MESFET for the first time in literature. Finally, the proposed model has been compared to the reported results to show the validity. The proposed model may be very useful for the designing of photonic MMIC’s and optical receivers using GaAs MESFET’s.     

一种间接获取大功率MESFET管芯S参数的新方法

文章测量了单胞，双胞，六胞大功率ＭＥＳＦＥＴ的Ｓ参数，通过精确的误差控制，进行数据处理，得到了单胞拟合成双胞，单胞拟合成六胞的Ｓ参数，通过比较得出了一种间接获取大功率管芯Ｓ参数的方法，实验证明，此方法简单可行。     

宽带GaAs MESFET开关模型

提出了一种 MESFET开关的模型——附加栅控开关模型 ,适用于 MMIC电路的设计 ,具有很好的宽带微波特性。在 0 .1～ 2 0 GHz频率范围内 ,器件测试值与模型模拟值吻合较好     

1mm SiC多指栅微波功率器件

研制了4H-SiC MESFET 1mm多栅器件. 通过对SiC关键工艺技术进行研究，设计出初步可行的工艺流程，并且制作出单栅宽100μm，总栅宽1mm，栅长0.8μm的n沟道4H-SiC MESFET，其微波特性测试结果为：在2GHz, Vds＝30V时，最大输出功率为1.14W，相应增益为4.58dB，功率附加效率为19%，漏极效率为28.7%.     

硫钝化GaAs MESFET的机理研究

研究了硫钝化对GaAs MESFET直流特性的影响,并通过对钝化前后击穿电压的分析,认为负电荷表面态的增加减弱了栅靠漏一侧的电场强度,是导致器件击穿电压升高的原因.     

GaAs－InP复合材料的外延生长方法及金属半导体场效应晶体管器件制备

提出了一种新的生长过渡层的方法，并利用低压金属有机气相外延技术在ＩｎＰ衬底上生长出高质量ＧａＡｓ外延材料，用Ｘ射线双晶衍射测得５μｍ厚ＧａＡｓ外延层的（００４）晶面衍射半峰高宽（ＦＷＨＭ）低至１４０ａｒｃｓｅｃ。并制出ＧａＡｓ金属半导体场效应晶体管（ＭＥＳＦＥＴ），其单位跨导为１００ｍｓ／ｍｍ，可满足与长波长光学器件进行单片集成的需要。     

Optimization of selective area growth of GaAs by low pressure organometallic vapor phase epitaxy for monolithic integrated circuits

GaAs MESFET device structures have been grown on silicon nitride or silicon dioxide masked 50 and 76 mm GaAs substrates by low pressure organometallic vapor phase epitaxy. Very smooth, featureless morphology and 100 percent selectivity of GaAs islands have been achieved over a range of growth conditions. Optimization of the GaAs p-buffer of the field effect transistor structure has led to improved device performance, including increased breakdown voltage. Device characteristics of the 0.5 μm gate low noise metal semiconductor field-effect transistors fabricated on these islands show good performance and wafer to wafer reproducibility on the second device lot.     

用于光电集成的GaAs/InP MESFET研究

提出了一种新的生长过渡层的方法，并利用低压金属有机气相外延技术在InP衬底上生长出高质量GaAs外延材料，用X射线双晶衍射测得5μm厚GaAs外延层的（004）品面行射半高峰宽（FWHM）低至140arcsee。并制出GaAs金属半导体场效应晶体管（MESFET），其单位跨导为100mS／mm，可满足与长波长光学器件进行单片集成的需要。