Effects of Mg Doping on Double Channel Layer Atmospheric Pressure-Plasma Enhanced Chemical Vapor Deposition Fabricated Amorphous InGaZnO Thin Film Transistors

Amorphous IGZO (a-IGZO) has been proved to be a suitable material for the channel layer in a thin film transistor, showing high mobility even in low temperature fabrication, device electrical characteristic exceeds a-Si or other metal oxide semiconductor materials. In this work, bottom gate top TFT is fabricated. With Atmosphere Pressure-PECVD (AP-PECVD), a-IGZO is deposited as device channel layer. A double channel layer is tested with Mg doping added in the bottom layer. This work focus on how the Mg doping concentration in the bottom layer affects device electrical characteristic. The result for best device characteristics is 5% Mg doping, showing highest mobility, lowest threshold voltage, and nearly 108 in Ion/Ioff. A suitable doping concentration can lower interface defect density and affect grain size, which both leads to a better device characteristics. However, device characteristics show sgn of degradation with excess doping concentration. IP 182.75.148.10 On: Fri, 04 Feb 2022 08:18:07 C i ht A i Sci ifi P bli h