In this work we analysed the performance of AlGaN/GaN HEMT based on the linearity metrics for variable source/drain spacing with a fixed gate length (1μm) using Sentaurus TCAD device simulator. Various figure of merits such as transconductance, higher order transconductance coefficients (gm1, gm 3), second/third-order voltage intercept point (VIP2/VIP3), third-order input intercept point (IIP3), third order intermodulation distortion (IMD3), and 1-dB compression point have been investigated and reported here. From the primary observation, it is found that the device with the source spacing (LSG=0.25 μm) and the drain spacing (LDG=0.75μm) for fixed gate length (Lg=1 μm) shows an improved device linearity as compared to the combination of LSG/LDG=0.5/0.5, 0.75/0.25, 1/1 μm. This study can be used in optimising and designing the HEMT structure for high frequency applications.

Source : An effect of source/drain spacing in AlGaN/GaN HEMT on linearity to improve device reliability | IEEE Conference Publication | IEEE Xplore