Demonstration of n-Ga2O3/p-GaN Diodes by Wet-Etching Lift-Off and Transfer-Print Technique

In this letter, a 400-nm-thick
$\beta $
-Ga
₂
O
₃
nanomembrane is extracted from an n-Ga
₂
O
₃
-on-silicon wafer by wet etching, and then transferred to a p-GaN/ sapphire wafer by transfer-print technique to fabricate n-Ga
₂
O
₃
/p-GaN heterojunction diodes. X-ray photoelectron spectroscopy (XPS) measurement is used to accurately confirm that the valence-band offset of the heterojunction is 1.41± 0.07 eV. The diodes exhibit excellent electrical properties including high rectification ratio (
${3.85}\times {10} ^{{6}}$
at ±5 V) and low reversed current density (
${1.51}\times {10} ^{-{7}}\,\,\text{A}\cdot $
cm
⁻²
at −5 V). The results show that the lift-off and transfer-print processes pave a new way for fabricating high-performance Ga
₂
O
₃
-based heterojunctions and bipolar devices.