Transient Characteristics of $\beta$-Ga$_2$O$_3$ Nanomembrane Schottky Barrier Diodes on Various Substrates

TL;DR

This study investigates how substrate material and nanomembrane thickness affect the transient electrical behavior of $eta$-Ga$_2$O$_3$ Schottky diodes, revealing the importance of thermal properties and heat dissipation for device performance.

Contribution

It systematically analyzes the impact of different substrates and nanomembrane thicknesses on the transient characteristics of $eta$-Ga$_2$O$_3$ Schottky diodes, highlighting phonon scattering and heat dissipation effects.

Findings

High-k substrates reduce transient delay times.

Thinner $eta$-Ga$_2$O$_3$ NMs improve heat dissipation.

Phonon scattering significantly influences transient behavior.

Abstract

In this paper, a transient delayed rising and fall time of $\beta$-Ga$_2$O$_3$ NMs Schottky barrier diodes (SBDs) formed on four different substrates (diamond, Si, sapphire, and polyimide) were measured using a sub-micron second resolution time-resolved electrical measurement system under a different temperature condition. The devices exhibited noticeably less-delayed turn-on-/off- the transient time when $\beta$-Ga$_2$O$_3$ NMs SBDs were transfer-printed on a high-k substrate. Furthermore, a relationship between the $\beta$-Ga$_2$O$_3$ NM thicknesses and their transient characteristics were systematically investigated and found that phonon scattering plays an important role in heat dissipation as the thickness of $\beta$-Ga$_2$O$_3$ NMs get thinner which is also verified by the Multiphysics simulator. Overall, our result reveals the impact of various substrates with different thermal properties and different \b{eta}- Ga2O3 NMs thickness with the performance of $\beta$-Ga$_2$O$_3$ NMs based devices. Hence, these results can guide further efforts us to optimize the performance of future $\beta$-Ga$_2$O$_3$ devices by maximizing heat dissipation from the $\beta$-Ga$_2$O$_3$ layer.