AVS 60th International Symposium and Exhibition
    Transparent Conductors and Printable Electronics Focus Topic Wednesday Sessions
       Session TC+EM+TF-WeM

Paper TC+EM+TF-WeM4
UV Radiation Effect on Electrical Characteristics of Passivated IGZO TFTs

Wednesday, October 30, 2013, 9:00 am, Room 102 B

Session: Oxide and Flexible Electronics
Presenter: Y.J. Tak, Yonsei University, Republic of Korea
Authors: Y.J. Tak, Yonsei University, Republic of Korea
D.H. Yoon, Yonsei University, Republic of Korea
S.H. Yoon, Yonsei University, Republic of Korea
U.H. Choi, Yonsei University, Republic of Korea
H.J. Kim, Yonsei University, Republic of Korea
Correspondent: Click to Email
Ultraviolet (UV) radiation effects have been intensively researched in oxide thin film transistors (TFTs). In general, UV radiation induces the increase of off-current and the existence of hump effect.[1] These changes of electrical properties in non-passivated oxide TFTs are almost recovered to original states.[2] However, back surface of oxide TFTs is sensitive to oxygen and humidity, passivation is key layer for stability and reliability on device. For this reason, we investigated the effects of post UV treatment on the SiO2 passivated indium gallium zinc oxide (IGZO) TFTs, specifically by irradiating UV spectrum of different wavelength, intensity, and treatment time. We performed light treatment of wavelength of 365 nm and 185 nm. And then varied power intensities were performed 64.66 mW/cm2, 0.9375 mW/cm2 respectively. These UV experiments were carried out with various treatment time of 10 min, 20 min, 30 min, and 60 min. As a result, the increment of off-current was shown which was higher in 185 nm radiated one than that of 365 nm, and increase of the intensity and treatment time led to increase in off-current and hump effect. Also, these changes were not restored to its original state after relaxation period. The result of experiment indicated that SiO2 passivated-TFTs need to block the UV radiation because of incompletely vanished hump effect that causes degardation on the devices.