The de-bias effect of gate current in InP HEMT MMICs

Increased gate current of InP HEMTs subjected to elevated temperature lifetest has been observed. The higher the temperature and the larger the gate periphery, the higher the gate current. On the other hand, gate resistors (Rg) are often used in the MMIC design for stability. As a result, the high gate current in conjunction with Rg de-biases the transistors in InP HEMT MMICs under elevated temperature lifetest. Accordingly, the evolution of DC parameters between discrete transistors and MMICs illustrates distinct difference. Furthermore, the de-bias effect of gate current in InP HEMT MMICs strongly depends on the lifetest temperature, gate periphery, and gate resistor. As a result, consideration of lifetest temperature, gate periphery, and gate resistors in InP HEMT MMICs is crucial in order to mitigate the de-bias effect induced by elevated temperature lifetest. In this paper, the de-bias effect of gate current in InP HEMT MMICs was illustrated for the first time.