고전압과 고전력 응용을 위한 $Al_{0.3}Ga_0.7N/GaN$ 이종접합 전계효과 트랜지스터의 제작 및 특성에 관한 연구

Studies on Fabrication and Characteristics of $Al_{0.3}Ga_0.7N/GaN$ Heterojunction Field Effect Transistors for High-Voltage and High-Power Applications

  • 김종욱 (LG저자기술원 소자재료연구소 RF소자그룹) ;
  • 이재승 (LG저자기술원 소자재료연구소 RF소자그룹) ;
  • 김창석 (LG저자기술원 소자재료연구소 RF소자그룹) ;
  • 정두찬 (LG저자기술원 소자재료연구소 RF소자그룹) ;
  • 이재학 (LG저자기술원 소자재료연구소 RF소자그룹) ;
  • 신진호 (LG저자기술원 소자재료연구소 RF소자그룹)
  • Kim, Jong-Wook (RF Devices Group, Devices and Materials Laboratory, LG Electronics Institute of Technology) ;
  • Lee, Jae-Seung (RF Devices Group, Devices and Materials Laboratory, LG Electronics Institute of Technology) ;
  • Kim, Chang-Suk (RF Devices Group, Devices and Materials Laboratory, LG Electronics Institute of Technology) ;
  • Jeong, Doo-Chan (RF Devices Group, Devices and Materials Laboratory, LG Electronics Institute of Technology) ;
  • Lee, Jae-Hak (RF Devices Group, Devices and Materials Laboratory, LG Electronics Institute of Technology) ;
  • Shin, Jin-Ho (RF Devices Group, Devices and Materials Laboratory, LG Electronics Institute of Technology)
  • 발행 : 2001.08.01

초록

분자선 결정 성장법을 이용하여 성장된 서로 다른 장벽층의 두께를 갖는 $Al_{0.3}Ga_{0.7}N$ heterojunction field effect transistors (HFETs) 를 제작하여 그 특성을 비교, 관찰하였다. $Al_{0.3}Ga_{0.7}N$층의 두께에 따른 특성의 비교로부터 최적의 2 차원 전자개스 (2 dimensional electron gas) 를 가질 수 있는 $Al_{0.3}Ga_{0.7}N$/GaN HFET 소자 구조를 얻을 수 있었다. $L_g=0.6$ ${\mu}m$$W_g=34\;{\mu}m$ $Al_{0.3}Ga_{0.7}N$/GaN (20 nm/2 mm) HFET에서 Imax ($V_{gs}=1\;V$) 와 $G_{m,maX}$는 각각 1.155 A/mm 및 250ms/${\mu}m$ 이었으며 $F_t=13$ GHz 와 $F_{max}=48$ GHz의 우수한 고주파 특성을 얻을 수 있었고 2 inch 기판상에서 제작된 소자들은 5% 이하의 매우 균일한 DC 특성을 나타내었다. 이와 더불어 게이트-드레인 간의 간격에 따른 소자의 특성을 관찰함으로서 소자의 항복전압과 고주파 특성과의 상관관계를 고찰하였다.

We report on the fabrication and characterization of $Al_{0.3}Ga_{0.7}N$ HFETs with different barrier layer thickness which were grown using plasma-assisted molecular beam epitaxy (PAMBE). The barrier thickness of $Al_{0.3}Ga_{0.7}N$/GaN HFETs could be optimized in order to maximize 2 dimensional electron gas induced by piezoelectric effect without the relaxation of $Al_{0.3}Ga_{0.7}N$ layer. $Al_{0.3}Ga_{0.7}N$/GaN (20 nm/2 mm) HFET with 0.6 ${\mu}m$-long and 34 ${\mu}m$-wide gate shows saturated current density ($V_{gs}=1\;V$) of 1.155 A/mm and transconductance of 250 ms/mm, respectively. From high frequency measurement, the fabricated $Al_{0.3}Ga_{0.7}N$/GaN HFETs showed $F_t=13$ GHz and $F_{max}=48$ GHz, respectively. The uniformity of less than 5% could be obtained over the 2 inch wafer. In addition to the optimization of epi-layer structure, the relation between breakdown voltage and high frequency characteristics has been examined.

키워드

참고문헌

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