Details

Autor(en) / Beteiligte

• Park, Jong Yul
• Min, Byoung‐Gue
• Lee, Jong‐Min
• Chang, Woojin
• Kang, Dong Min
• Jang, E‐San
• Kim, Junhyung
• Kim, Jeong‐Gil

Titel

Optimized recess etching criteria for T‐gate fabrication achieving ft = 290 GHz at Lg = 124 nm in metamorphic high electron mobility transistor with In0.7Ga0.3As channel

Ist Teil von

• Electronics letters, 2023-07, Vol.59 (14), p.n/a

Ort / Verlag

Stevenage: John Wiley & Sons, Inc

Erscheinungsjahr

2023

Quelle

Wiley Online Library Journals

Beschreibungen/Notizen

• The authors propose criteria for recess etching to fabricate T‐gate used in InGaAs high electron mobility transistors (HEMTs). By patterning additional rectangular pads on the source and drain metals in the e‐beam lithography step, it is possible to measure the drain‐to‐source resistance (Rds) and current (Ids). The ratio (Γ) of before and after etching for each Rds and Ids can be used as criteria to determine the point in time to stop etching. By performing recess etching with Γ= 1.97 for Rds and Γ= 0.38 for Ids on an epiwafer having cap doping concentration of 2 × 1019 cm−3 and channel indium content of 0.7, the authors have fabricated InGaAs metamorphic high electron mobility transistor (mHEMT) device showing gm,max= 1603 mS/mm and ft= 290 GHz at Lg= 124 nm. The criteria presented can be applied to InGaAs HEMTs with various epitaxial structures. The criteria presented in this article suggest using the ratio of before and after etching for each drain‐to‐source resistance and current to determine the optimal timing for stopping the recess etching process. By referring these criteria, it would be helpful to fabricate high‐performance InGaAs HEMTs with different epitaxial structures.