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Abstract A free‐standing β‐Ga2O3, also called β‐Ga2O3nanomembrane (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‐Ga2O3NM under strain conditions have not yet investigated. In this paper, the electrical properties of β‐Ga2O3NM 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‐Ga2O3NM causes a severe property degradation due to higher resistance and uneven charge distribution in β‐Ga2O3NM which is also confirmed by the multiphysics simulation. Interestingly, the degraded performance in β‐Ga2O3NM is substantially recovered by introducing excessive OH‐bonds in fractured β‐Ga2O3NM 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‐Ga2O3samples exhibit reliable and stable recovered electrical properties up to ≈90% of their initial values. Therefore, this result offers a viable route for utilizing β‐Ga2O3NMs as a next‐generation material for a myriad of high‐performance flexible electronics and optoelectronic applications.
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Surface Adsorption and Air Damping Behavior of β‐Ga 2 O 3 Nanomechanical Resonators
Abstract Beta gallium oxide (β‐Ga2O3) has emerged as a highly promising semiconductor material with an ultrawide bandgap ranging from 4.5 to 4.9 eV for future applications in power electronics, optoelectronics, as well as gas and ultraviolet (UV) radiation sensors. Here, surface adsorption and air damping behavior of doubly clamped β‐Ga2O3nanomechanical resonators are probed and systemically studied by measuring the resonance characteristics under different gas and pressure conditions. High responsivities of resonance to pressure are obtained by heating the devices up to 300 °C to induce an accelerated adsorption–desorption process. The initial surface conditions of the β‐Ga2O3thin film play important roles in affecting the resonant behavior. UV ozone treatment proves effective in altering the initial surface conditions of β‐Ga2O3nanosheets by eliminating physisorbed contaminants and filling oxygen vacancy defects residing on the surface, resulting in a consequential and discernible modification of the resonance behavior of β‐Ga2O3nanomechanical resonators. The surface adsorption and desorption processes in β‐Ga2O3demonstrate clear reversibility by exposing the UV treated β‐Ga2O3to air. This study attains first‐hand information on how the surface conditions of β‐Ga2O3affect its mechanical properties, and helps guide future development of transducers via β‐Ga2O3nanoelectromechanical systems (NEMS) for pressure sensing applications, especially in harsh environments.
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- Award ID(s):
- 2221881
- PAR ID:
- 10486877
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Technologies
- Volume:
- 9
- Issue:
- 5
- ISSN:
- 2365-709X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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