Demonstration of One Transistor-One Diode (1T1D) p-GaN/AlGaN/GaN Memory Cell

This letter demonstrates a one transistor - one diode p-GaN/AlGaN/GaN (1T1D) memory cell for potential applications in harsh-environment GaN integrated circuits. The 1T1D memory consists of a metal/insulator/ p-GaN gate HEMT (MIP-HEMT) and a p-GaN/AlGaN/GaN heterojunction diode (D1). The writing ‘0’ process (W0) is accomplished by the injection of holes from the p-GaN through the parasitic heterojunction diode within the transistor (D2), resulting in a storage of negative charges inside the p-GaN layer. The writing ‘1’ process (W1) involves the refill of holes into the p-GaN gate via D1. A large ${V} _{\mathbf {\textit {TH}}}$ window (>5 V) is obtained, and the current margin ( ${I}_{\mathbf {{1}}}$ – ${I}_{\mathbf {{0}}}$ ) is ~30 mA/mm.