Growth behavior of GaN on AlN for fully coalesced channel of AlN-based HEMT. (6th November 2019)

• Record Type: Journal Article
• Authors: Choi, Uiho; Lee, Kyeongjae; Kwak, Taemyung; Jung, Donghyeop; Jang, Taehoon; Nam, Yongjun; So, Byeongchan; Kim, Hyun-Seop; Cha, Ho-Young; Kang, Myoung-Jin; Seo, Kwang-Seok; Nam, Okhyun
• Is Part Of: Japanese journal of applied physics. Volume 58:Number 12(2019)
• Publication Date: 2019-11-06
• Subjects: Physics -- Periodicals; 621.05
• DOI: 10.7567/1347-4065/ab4df3
• Languages: English
• ISSNs: 0021-4922

Abstract

Abstract: We investigated the growth behavior of GaN grown on AlN along with V/III ratio and pressure variation, and found out the lateral growth regime for the fully coalesced channel layer of the AlN-based double-hetero structure high electron mobility transistor (HEMT). When the V/III ratio increases and pressure decreases, compressive stress in the GaN channel increases, and pit formation occurs to release the stress. The AlN-based HEMT structure was grown and the device was fabricated with an optimized channel layer. The two-dimensional electron gas mobility, sheet density, and sheet resistance were 1480 cm 2 V −1 s −1, 1.32 × 10 13 cm −2, and 319 Ω/sq., respectively, at room temperature. The device was characterized; direct current output result showed that the maximum current was ∼620 mA mm −1, on-resistance was 6.4 Ω mm, transconductance was ∼140 mS mm −1, and current on/off ratio was ∼10 4, respectively.