Investigation of Nano‐Gaps in Fractured β‐Ga 2 O 3 Nanomembranes Formed by Uniaxial Strain

Abstract A free‐standing β‐Ga 2 O 3 , also called β‐Ga 2 O 3 nanomembrane (NM), is an important next‐generation wide bandgap semiconductor that can be used for myriad high‐performance future flexible electronics. However, details of structure‐property relationships of β‐Ga 2 O 3 NM under strain conditions have not yet investigated. In this paper, the electrical properties of β‐Ga 2 O 3 NM under different uniaxial strain conditions using various surface analysis methods are systematically investigated and layer‐delamination and fractures are revealed. The electrical characterization shows that the presence of nanometer‐sized gaps between fractured pieces in β‐Ga 2 O 3 NM causes a severe property degradation due to higher resistance and uneven charge distribution in β‐Ga 2 O 3 NM which is also confirmed by the multiphysics simulation. Interestingly, the degraded performance in β‐Ga 2 O 3 NM is substantially recovered by introducing excessive OH‐bonds in fractured β‐Ga 2 O 3 NM via the water vapor treatment. The X‐ray photoelectron spectroscopy study reveals that a formation of OH‐bonds by the water vapor treatment chemically connects nano‐gaps. Thus, the treated β‐Ga 2 O 3 samples exhibit reliable and stable recovered electrical properties up to ≈90% of their initial values. Therefore, this result offers a viable route for utilizing β‐Ga 2 O 3 NMs as a next‐generation material for a myriad of high‐performance flexible electronics and optoelectronic applications.