1. High Performance E-Mode HEMT and the Application 2004-21510 박 상 호

2. Contents 1. InAlAs/InGaAs E-Mode HEMT 2. Advantages & Disadvantages of E-HEMT 3. Processes of E-HEMT 1) Pt-Buried Gate 2) Two-Step Recessed Gate 3) Selective Hydrogen Treatment 4. Applications - DCFL

3. InAlAs/InGaAs E-Mode HEMT Threshold voltage is positive at V gs =0 Normally off state

4. Advantages & Disadvantages of E-Mode HEMT  Advantages 1) 1 개의 power supply 만 요구 2) Large gm, ft, fmax  Disadvantages 1) large Rs 2) difficult process

5. Pt-buried gate Side etching effect  depleted gate periphery  high resistive 대안 : Pt-based gate 를 이용한 high schottky barrier height 구현

6. Cont. Pt Channel Buried gate front after annealing

7. Cont. DC Performance

8. Cont. RF Performance

9. Two Step Recessed Gate

10. Cont.

11. DC&RF Performance(0.1um gate length)

12. Selective Hydrogen Treatment Low etch selectivity & poor adhesion  difficult to fabricate E-HEMT Without any recess etching and schottky metal  SHT process

13. Applications-DCFL For high speed and low power dissipation used D,E- HEMT Advantage : Power 소모 감소 single P.S 사용  small chip size 문제점 : 하나의 chip 에 E,D-HEMT 를 동시에 구현 하는 것이 어렵다.(different gate recess depth)  selective ion implantation 으로 해결 Selective ion implantation ;wafer 상에 E-HEMT fab.  selective ion implantation  D-HEMT 구현

14. DC & RF Performance

15. Reference 1. Mahajan, “ Enhancement mode High electron mobility transistor(E- HEMT ’ s)lattice-matched to InP ”, IEEE Trans.E.D., 1998 2. Suemitsu, “ High-performance 0.1um gate enhancement mode InAlAs/InGaAs HEMT ’ s using two step recessed gate technology ”, IEEE Trans.E.D., 1999 3. Chen, “ High performance InP-based enhancement – mode HEMT ’ s using non- alloyed ohmic contacs and Pt-based buried gate technology ”, IEEE Trans.E.D., 1996 4. I-H Kang, “ Enhancement mode p-HEMT using selective hydrogen treatment ”, Electronics lett.,2003 5. Chan, “ Enhancement and depletion mode AlGaAs/In0.15Ga0.85As HEMT ’ s fabricated by selective ion implantation ”, Electronics lett.,1993 6. Chen, “ Improved source resistance in InP-based enhancement-mode HEMTs for high speed digital applications ”, Electronics lett.,1995 7. Mahajan, “ InP based HEMT for high speed, low power circuit applications ”, Electronics lett.,1998