Negative gate bias and light illumination-induced hump in amorphous InGaZnO thin film transistor.
While observing the transfer characteristics of a-IGZO TFTs, it was noticed that a hump occurred in the subthreshold regime after light and bias stress. This study analyzes the mechanism of the hump occurrence. It was determined that hump characteristics were related with parasitic TFTs which formed at the peripheral edges parallel with the channel direction. It seems that the negative shift of the transfer characteristics of parasitic TFTs was larger than that of the main TFT under light and bias stress. Therefore, the difference in the negative shift between the main TFT and the parasitic TFT was the origin of the hump occurrence. We investigated the instability of a-IGZO TFTs under negative gate bias with light illumination for various channel structures in order to verify the above mechanism.
School of Electronics, Telecommunications and Computer Engineering, Korea Aerospace University, Goyang, 412-791, Korea.
Jae-Hong
JH
Jeon
Seung-Bum
SB
Seo
Han-Sung
HS
Park
Hee-Hwan
HH
Choe
Jong-Hyun
JH
Seo
Kee-Chan
KC
Park
Sang-Hee Ko
SH
Park
D004574:Electromagnetic Fields; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005708:Gallium / Q000737:chemistry* / Q000528:radiation effects; D007204:Indium / Q000737:chemistry* / Q000528:radiation effects; D008027:Light; D008029:Lighting / Q000379:methods; D008422:Materials Testing; D008567:Membranes, Artificial; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000528:radiation effects; D014173:Transistors, Electronic; D015034:Zinc Oxide / Q000737:chemistry* / Q000528:radiation effects
D008567:Membranes, Artificial; D007204:Indium; C038863:gallium oxide; C047711:indium oxide; D005708:Gallium; D015034:Zinc Oxide