Studies on Modification of Channel Material and Gate Recess Structures in Metamorphic HEMT
In this study,we have performed both the channel modification of the conventional MHEMT (Metamorphic High Electron Mobility Transistor) and the variation of gate recess. The modified channel consists of the ln0.53Ga0.47 As and the InP layers. Since InP has lower impact ionization coefficient than In0.53Ga0.47As,we have adopted the InP-composite channel in the MHEMT. Also,the gate recess width is both functions of breakdown and RFcharacteristic of a HEMT structure. Therefore,we have studied the breakdown and RF characteristic for various gate recess widths of MHEMTs. We have compared breakdown characteristic of the lnP-composite channel with that of conventional MHEMTs. It is shown that on and off state breakdown voltages of the lnP-composite channel MHEMT were increased by about 20 and 27 %,respectively,compared with the conventional structure. Also,breakdown voltage of the lnP-composite channel MHEMT was increased with increasing gate recess width. The fr was increased with decreasing the gate recess width,whereas fmax was increased with increasing the gate recess width. Also,weextracted small-signal parameters. It was shown that Gd of the InP-composite channel MHEMT is decreased about by 30 % compared with the conventional MHEMT. Therefore,the suppression of the impact ionization in the InP-composite channel increases the breakdown voltage and decreases the output conductance.
Seok Gyu Choi Young Hyun Baek Jung Hun Oh Min Han Seok Ho Bang Byoung Chul Jun Hyun Chang Park Jin Koo Rhee
Millimeter-wave INnovation Technologyresearch center (MINT),Dongguk University Millimeter-wave INnovation Technology research center (MINT),Dongguk University
国际会议
2008 Global Symposium on Millimeter Waves(GSMM 2008)(2008全球毫米波学术大会)
南京
英文
6-9
2008-04-21(万方平台首次上网日期,不代表论文的发表时间)