Polymer Doping Enables a Two‐Dimensional Electron Gas for High‐Performance Homojunction Oxide Thin‐Film Transistors
Abstract
High‐performance solution‐processed metal oxide (MO) thin‐film transistors (TFTs) are realized by fabricating a homojunction of indium oxide (In2O3) and polyethylenimine (PEI)‐doped In2O3 (In2O3:x% PEI, x = 0.5–4.0 wt%) as the channel layer. A two‐dimensional electron gas (2DEG) is thereby achieved by creating a band offset between the In2O3 and PEI‐In2O3 via work function tuning of the In2O3:x% PEI, from 4.00 to 3.62 eV as the PEI content is increased from 0.0 (pristine In2O3) to 4.0 wt%, respectively. The resulting devices achieve electron mobilities greater than 10 cm2 V−1 s−1 on a 300 nm SiO2 gate dielectric. Importantly, these metrics exceed those of the devices composed of the pristine In2O3 materials, which achieve a maximum mobility of ≈4 cm2 V−1 s−1. Furthermore, a mobility as high as 30 cm2 V−1 s−1 is achieved on a high‐k ZrO2 dielectric in the homojunction devices. This is the first demonstration of 2DEG‐based homojunction oxide TFTs via band offset achieved by simple polymer doping of the same MO material.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Nov 29, 2018
- Source ID
- 10.1002/adma.201805082
Entities
People
- Antonio Facchetti
- Binghao Wang
- Gang Wang
- Li Zeng
- Mark Hersam
- Michael Bedzyk
- Tobin J. Marks
- Vinod K Sangwan
- Wei Huang
- Yan Huang
- Yao Chen
- Zhiyun Lu
Organizations
- Air Force Office of Scientific Research
- China Scholarship Council
- Northwestern University
- Sichuan University