Improved Stability of GaN MIS-HEMT With 5-nm Plasma-Enhanced Atomic Layer Deposition SiN Gate Dielectric

Abstract

In this work, characterizations are performed to investigate the stability of an mm-wave GaN metal-insulator-semiconductor HEMT. Bias temperature instability (BTI) experiment conducted at various voltages and temperatures show a highly stable threshold voltage ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V}_{\text {TH}}$ </tex-math></inline-formula> ) with both positive BTI (PBTI) and negative BTI (NBTI) attributing to the high quality of SiN gate dielectric. In addition, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V}_{\text {TH}}$ </tex-math></inline-formula> shift ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${\Delta } {V}_{\text {TH}}$ </tex-math></inline-formula> ) under reverse-bias step-stress is further monitored, achieving small <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${\Delta } {V}_{\text {TH}} &lt; {0.1}$ </tex-math></inline-formula> V and a recoverable behavior below <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V}_{\text {D}}$ </tex-math></inline-formula> , stress = 60 V. After 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sup> s of stress at 175°C, under the OFF-state high drain-bias, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${\Delta } {V}_{\text {TH}}$ </tex-math></inline-formula> is 0.15 V, and a larger <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V}_{\text {TH}}$ </tex-math></inline-formula> shift (0.23 V) is observed under On-state drain-bias of 28 V due to the high electric-field. According to the time-dependent dielectric breakdown prediction, +3.0 V gate voltage stress at a failure rate of 0.01 % can be extrapolated for mm-wave MIS-HEMT. These findings guarantee a good stability for the device utilized in power amplifier applications.