Multi-Channel AlGaN/GaN Lateral Schottky Barrier Diodes on Low-Resistivity Silicon for Sub-THz Integrated Circuits Applications

This paper presents novel multi-channel RF lateral Schottky-barrier diodes (SBDs) based on AlGaN/GaN on low resistivity (LR) ( ${\sigma }={0.02}\,\,{\Omega }$ .cm) silicon substrates. The developed technology offers a reduction of 37 % in onset voltage, $\text{V}_{{{ON}}}$ (from 1.34 to 0.84 V), and 36 % in ON-resistance, $\text{R}_{{{ON}}}$ (1.52 to 0.97 to ${\Omega }$ .mm) as a result of lowering the Schottky barrier height, ${\Phi }_{\text {n}}$ , when compared to conventional lateral SBDs. No compromise in reverse-breakdown voltage and reverse-bias leakage current performance was observed as both multi-channel and conventional technologies exhibited $\text{V}_{{{BV}}}$ of ( $\text{V}_{{ {BV}}}>{30}$ V) and $\text{I}_{\text {R}}$ of ( $\text{I}_{{R}}< {38}~{\mu }\text{A}$ /mm), respectively. Furthermore, a precise small-signal equivalent circuit model was developed and verified for frequencies up to 110 GHz. The fabricated devices exhibited cut-off frequencies of up to 0.6 THz, demonstrating the potential use of lateral AlGaN/GaN SBDs on LR silicon for high-efficiency, high-frequency integrated circuits applications.