Effects of microwave annealing on electrical enhancement of amorphous oxide semiconductor thin film transistor

Abstract

By using microwave annealing technology instead of thermal furnace annealing, this work elucidates the electrical characteristics of amorphous InGaZnO thin film transistor (a-IGZO TFT) with a carrier mobility of 13.5 cm2/Vs, threshold voltage of 3.28 V, and subthreshold swing of 0.43 V/decade. This TFT performance with microwave annealing of 100 s is well competitive with its counterpart with furnace annealing at 450 °C for 1 h. A physical mechanism for the electrical improvement is also deduced. Owing to its low thermal budget and selective heating to materials of interest, microwave annealing is highly promising for amorphous oxide in semiconductor TFT manufacturing.

Microwave Annealing Effect for Highly Reliable Biosensor: Dual-Gate Ion-Sensitive Field-Effect Transistor Using Amorphous InGaZnO Thin-Film Transistor

“…This indicates that the microwave annealing process eliminates defects inside the device more effectively than the furnace annealing process. 25,26 Device A had a high field-effect mobility of 9.51 cm 2 /V·s (drain voltage = 50 mV), a good subthreshold swing (SS) of 135 mV/ dec, a low threshold voltage (V th ) of 0.99 V, and an excellent on/off current ratio of 1.18 × 10 8 .…”

Improvement of Device Characteristic on Solution-Processed InGaZnO Thin-Film-Transistor (TFTs) using Microwave Irradiation

“…Compared to the conventional furnace-annealed devices, the a-IGZO TFTs annealed by microwave irradiation exhibited better electrical characteristic in terms of field effect mobility, SS, and on/off current ratio, although the annealing temperature of the microwave irradiation process was much lower than that of furnace annealing. This is because the microwave irradiation process enhanced the bonding of the oxygen ions and effectively eliminated the defects in the channel layer [11,12]. conventional [9] IGZO One of the most important issues in a-GIZO TFTs is reliability.…”

Poly(4-vinylphenol) gate insulator with cross-linking using a rapid low-power microwave induction heating scheme for organic thin-film-transistors

“…Because, using microwave irradiation for heating is limited by its selective-heating characteristic that the energy cannot be absorbed by some materials, such as insulators. 19 In addition, the high microwave power (500 W-2000 W) reported in these studies was a serious issue.…”

“…[18][19][20] In previous study, 18 the microwave annealing scheme was usually used for semiconductor annealing (e.g., Silicon, IGZO, ZnO, etc.). Because, using microwave irradiation for heating is limited by its selective-heating characteristic that the energy cannot be absorbed by some materials, such as insulators.…”