Projected Cost of Gallium Oxide Wafers from Edge-Defined Film-Fed Crystal Growth

Abstract

Gallium oxide (Ga 2 O 3 ) is an emerging ultra-wide bandgap semiconductor that has unique properties ideal for high-power, high-temperature, optoelectronic, and sensing applications and has piqued interest over the last decade. It has the potential to be technologically and economically superior to commercially available wide bandgap semiconductor materials, such as silicon carbide and gallium nitride, because its wider bandgap enables increased breakdown voltages and lower on-state resistances, and its ability to be grown from melt enable costcompetitive economics. In this study, we present a techno-economic analysis that projects the cost of 6″ β-Ga 2 O 3 wafers fabricated from crystals grown via edge-defined film-fed growth (EFG). At a manufacturing volume of 5000 wafers per month, we predict a unit cost of $320 for a 6″ EFG grown β-Ga 2 O 3 epi-wafer. We determine that, when calculated using 2021 iridium crucible costs, EFG has a 2× cost advantage compared to previously reported epi-wafers grown via the Czochralski (CZ) method. We further identify key cost parameters for 6″ β-Ga 2 O 3 epi-wafers and present cost-sensitivity analysis of their impact on the final cost.

Low Interface Resistance in Epitaxial β-Ga2O3 Vertical Power Diodes on Silicon (100) Using TiN Buffer

“…(b) PFOM cost for single crystal and integrated semiconductors. (c) Effective thermal conductivity of β-Ga 2 O 3 on silicon substrate. − …”

“…We use the PFOM max cost (Figure b), i.e., PFOM max per $, as a metric to factor in the substrate cost. While the projected PFOM cost of 19 GW/$ for β-Ga 2 O 3 on native substrate , is promising, it can nearly double by integrating β-Ga 2 O 3 onto low-cost silicon (assuming the cost < 1 $/cm 2 , similar to device-grade heteroepitaxial GaN-on-Si). Beyond the cost advantage, β-Ga 2 O 3 -on-Si leverages the maturity and scalability of established silicon technology and paves the way for integration of control circuits on the same chip.…”

A landscape of β-Ga2O3 Schottky power diodes

“…With an E cr approximately three times that of SiC and GaN, β-Ga 2 O 3 offers greater intrinsic power conversion efficiencies and further expansion of the operating-voltage-switching-frequency power electronics application space. Melt-grown native substrates are available for β-Ga 2 O 3 , indicating a path to commercially viable β-Ga 2 O 3 devices [7,8] . Due to its wide bandgap, broadband transparency, low cost, and high thermal/chemical stability, β-Ga 2 O 3 has also emerged as a new platform for UV-vis nonlinear optics and integrated photonics such as waveguides and solar-blind photodetectors [9,10] .…”

Defect Chemistry and Doping of Ultrawide Band Gap (III)BO3 Compounds

“…For example, facile growth of β-Ga 2 O 3 crystals has enabled 6-in. wafers on native substrates, which are projected to be 3–5 times less expensive to fabricate than SiC. , However, Ga 2 O 3 and other emerging UWBG semiconductors have their own challenges. Commercialization of these materials is hindered by synthesis at scale (diamond, BN), lack of large suitable substrates (AlN, BN), poor thermal conductivity (Ga 2 O 3 ), and issues with doping to desired carrier concentrations (Ga 2 O 3 , AlN) …”