The Impact of Substrates on the Performance of Top-Gate p-Ga203 Field-Effect Transistors - Record High Drain Current of 980 mA/mm on Diamond
At a Glance
Section titled “At a Glance”| Metadata | Details |
|---|---|
| Publication Date | 2018-06-01 |
| Authors | Jinhyun Noh, Mengwei Si, Hong Zhou, Marko J. Tadjer, Peide D. Ye |
| Institutions | United States Naval Research Laboratory |
| Citations | 16 |
Abstract
Section titled “Abstract”For high power devices, monolithic <tex xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”>$\beta$</tex> -Ga203 has been identified as an emerging ultra-wide bandgap semiconductor material because it has a large bandgap of 4.8 eV and a high breakdown electric field of 8 MV/cm [1]. <tex xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”>$\beta$</tex> -Ga203 has also the potential to realize low-cost large-size native bulk substrates by melt-grown methods [2], [3]. However, the output power density and the maximum drain current density of <tex xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”>$\beta$</tex> -Ga203 devices can be seriously limited due to its low thermal conductivity <tex xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”>$(\kappa$</tex> of 10-25 W/m·K and self-heating effect (SHE) [4], [5]. If the heat from the channel cannot be well dissipated through the substrate, SHE can lead to significant channel temperature increase, thus degrade the device performance and the long-term reliability [6]. In order to overcome this material constraint, we explored nano-membrane transferring technique and studied <tex xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”>$\beta$</tex> -Ga203 nano-membrane field-effect transistors (FETs) on different foreign substrates such as sapphire <tex xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”>$(\kappa=40\ \mathrm{W}/\mathrm{m}\cdot \mathrm{K})$</tex> and Si0 <inf xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”>2</inf> /Si <tex xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”>$(\kappa=1.5\ \mathrm{W}/\mathrm{m}\cdot \text{K for}\ 270\ \text{nm SiO}_{2})$</tex> and compared the impact of these substrates on the device performance [7]-[9]. In this work, furthermore, we demonstrate the first B-Ga203 Fet on a diamond substrate with an extremely high thermal conductivity of <tex xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”>$1,000\sim 2,200\ \mathrm{W}/\mathrm{m}\cdot \mathrm{K}$</tex> [10] and compare with devices on a sapphire or Si0 <inf xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”>2</inf> /Si substrate.