Flexible Electronics: Investigation of Nano‐Gaps in Fractured β‐Ga₂O₃ Nanomembranes Formed by Uniaxial Strain (Adv. Electron. Mater. 2/2021)

Abstract

β‐Ga2O3 nanomembranes are a quasi‐two‐dimensional form of bulk β‐Ga2O3. In article number 2000763, Jung‐Hun Seo and co‐workers present a systematical investigation of the layer delaminations and fractures in β‐Ga2O3 nanomembrane under strain. The performance degradation is recovered by a water vapor treatment, meaning that this result provides a viable route for utilizing β‐Ga2O3 nanomembrane as a material for future high‐performance flexible electronics.

Transient characteristics of β-Ga2O3 nanomembrane Schottky barrier diodes on various substrates

“…The β-Ga 2 O 3 NMs were created by clipping several large segments from the bulk substrate at an angle of 77 • , followed by an exfoliation using a well-known taping method. β-Ga 2 O 3 segments were easily mechanically exfoliated in the [100] direction due to the weak binding energy in this direction [24][25][26]32]. In this step, various β-Ga 2 O 3 NM thicknesses can be created by adjusting exfoliation times.…”

“…After the transfer processes were completed, ohmic metal and Schottky metal electrodes deposition processes were conducted. Prior to ohmic metal deposition, a plasma treatment was performed on β-Ga 2 O 3 NMs by a BCl 3 /Ar plasma treatment using a reactive ion etcher to achieve ohmic contact and to avoid an additional high-temperature annealing process [25][26][27]. After that, an ohmic metal stack (Ti/Au = 20/100 nm) and a Schottky metal stack (Ti/Pt/Au = 20/30/100 nm) were then deposited to complete the device fabrication.…”

“…Recently, another novel route to manage a β-Ga 2 O 3 thermal property was to use a sub-micron thin and freestanding format of β-Ga 2 O 3 , which also called β-Ga 2 O 3 nanomembrane (NM). β-Ga 2 O 3 NMs can be tailored as a desired shape and then transfer-printed onto any new substrates [23][24][25][26][27]. Thus, efficient heat dissipation from β-Ga 2 O 3 is expected when β-Ga 2 O 3 NMs are transfer-printed on a highk substrate.…”