Local strain modification effects on global properties of AlGaN/GaN high electron mobility transistors

Performance and reliability of microelectronic devices are governed by the mechanical strain within device layers. Typically, this is studied with uniformly distributed applied externally or internally. The focus study on AlGaN/GaN high electron mobility transistors (HEMTs), which expected to be more sensitive due its piezo-resistive piezo-electric nature. Accordingly, we hypothesize that even small but localized may have significant impact overall behavior a HEMT. To investigate hypothesis, introduce highly relief milling 20 × 30 μm2 micro trench about 70 μm deep backside an 800 840 size HEMT die. resulting local relaxation in-plane residual was mapped using micro-Raman technique. Our results show decrease only 0.02% can output saturation current up ~20%. drop attributed reduced two-dimensional gas (2DEG) sheet carrier density in However, mechanistic process also causes defect generation at interfaces, increases leakage current. technique for re-distribution could effective tool surrogate influence inherent build-up across channel electronic devices.