Structural and Electronic Properties of Polycrystalline InAs Thin Films Deposited on Silicon Dioxide and Glass at Temperatures below 500 °C

Polycrystalline indium arsenide (poly InAs) thin films grown at 475^◦C by metal organic vapor phase epitaxy (MOVPE) are explored as possible candidates for low-temperature-grown semiconducting materials. Structural and transport properties of the films are reported, with electron mobilities of ~100 cm²/V·s achieved at room temperature, and values reaching 155 cm²/V·s for a heterostructure including the polycrystalline InAs film. Test structures fabricated with an aluminum oxide (Al₂O₃ ) top-gate dielectric show that transistor-type behavior is possible when poly InAs films are implemented as the channel material, with maximum I_ON/I_OFF > 250 achieved at −50^◦C and I_ON/I_OFF = 90 at room temperature. Factors limiting the I_ON/I_OFF ratio are investigated and recommendations are made for future implementation of this material.