  p-type doping from the dielectric/semiconductor interface of a SnO2 thin film
transistor (TFT) has been utilized to develop high carrier mobility balanced
ambipolar oxide-transistor. To introduce this interfacial-doping, bottom-gate
top-contact TFTs have been fabricated by using two different ion-conducting
oxide dielectrics which contain trivalent atoms. These ion-conducting
dielectrics are LilnO2 and LiGaO2 respectively, containing mobile Li+ ion.
During SnO2 thin film fabrication on top of the ionic dielectric, those
trivalent atoms allow p- doping to the interfacial SnO2 layer to introduce the
hole conduction in channel of TFT. To realize this interfacial doping
phenomena, a reference TFT has been fabricated with Li2ZnO2 dielectric under
the same condition that contains divalent zinc (Zn) atom. Our comparative
electrical data indicates that TFTs with LilnO2 and LiGaO2 dielectric are
ambipolar in nature whereas, TFT with Li2ZnO2 dielectric is a unipolar
n-channel transistor which reveals the interfacial doping of SnO2. Most
interestingly, by using LilnO2 dielectric, we are capable to fabricated 1.0 V
balanced ambipolar TFT with a high electron and hole mobility values of 7 cm2
V-1 s-1and 8 cm2 V-1 s-1 respectively with an on/off ratio >102 for both
operations which has been utilized for low-voltage CMOS inverter fabrication.
