2026-06-15 物質・材料研究機構
図: Si(111)上に、アモルファスライク中間層(AL-IL層)を介してGaN膜がエピタキシャル成長するイメージ
＜関連情報＞
- https://www.nims.go.jp/press/2026/06/202606150.html
- https://advanced.onlinelibrary.wiley.com/doi/10.1002/apxr.70143
シリコンウェハ上に垂直GaNデバイスを実現する高度なエピタキシャル戦略 An Advanced Epitaxial Strategy Enabling Vertical GaN Devices on Silicon Wafers
Fumio Kawamura, Takeyoshi Onuma, Kazutaka Mitsuishi
Advanced Physics Research Published: 29 May 2026
DOI:https://doi.org/10.1002/apxr.70143
ABSTRACT
While vertical gallium nitride (GaN)-on-silicon architectures promise a transformative leap in cost-effective power electronics and high-resolution micro-LEDs, their deployment remains bottlenecked by the high electrical resistance of conventional epitaxial buffer layers. Here, a universal and straightforward sputtering-based strategy is presented to realize high-quality GaN epitaxial films on Si(111) substrates characterized by exceptionally low vertical resistance, ohmic behavior, and robust thermal stability. This technique centers on the in situ formation of a sub-nanometer (∼0.5 nm) silicide-based template via rapid thermal annealing—a method demonstrating unprecedented versatility across 25 different metallic species. Scanning transmission electron microscopy (STEM) reveals that a unique amorphous-like interlayer (AL-IL) effectively accommodates lattice mismatch and relaxes epitaxial strain. These AL-IL templates further serve as high-performance platforms for metalorganic chemical vapor deposition (MOCVD) overgrowth, successfully bridging the gap between scalable, low-cost fabrication and device-grade vertical performance.
