Complementary Thin-Film Electronics Based on n-Channel ZnO and p-Channel ZnTe

Abstract

In this letter, we report on the fabrication of ZnO and ZnTe thin-film transistors (TFTs) on SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> /Si substrates in a bottom-gate configuration. The ZnO TFT devices exhibit field effect mobility of mu ~ 4 cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> /V middot s and an on/off current ratio exceeding 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">9</sup> . The on/off-current ratio of the ZnTe devices was found to be 100, limited by the off current. Incorporation of the ZnTe and ZnO TFTs in a complementary logic circuit demonstrates inverter behavior with a high output voltage of V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">OH</sub> > 14 V and low output voltage of V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">OL</sub> < 0.2 V for a supply voltage of 15 V. The small signal gain for the transfer characteristic is found to be dV <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">out</sub> / dV <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in</sub> = -5 at V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in</sub> = 6 V.