Boosting Visible Light Detectability of In-ga-zn-o Phototransistor with Additional Absorption Layer

Date(s):

Location:
Jacobs Hall, Henry Booker Room 2512, Jacobs School of Engineering, 9500 Gilman Dr, La Jolla, San Diego, California 92093

Sponsored By:
Professor Tina Ng

Speaker(s):
Prof. Hyun Jae Kim
School of Electrical & Electronic Engineering
Yonsei University, Seoul, Republic of Korea
Prof. Hyun Jae Kim

Abstract:

Recently, oxide semiconductors have become promising alternatives to Si-based semiconductors due to their outstanding properties such as high transparency, possibility of large area fabrication, low leakage current, and low process temperature. Based on these advantages, oxide semiconductors have been used in a variety of applications from the display area to solar cells and sensors. Among numerous types of applications, phototransistors for photo-sensing, which detect the shape, state, and movement of objects, have been attracted attention because of the necessity in all new electronic devices due to the trend of automation such as smart windows and smart glass. However, oxide phototransistor could hardly detect visible light because of its wide band gap of more than 3 eV. Therefore, extra process such as addition of an absorption layer or modification of layers is essential in sensing visible light using oxide phototransistor. These phototransistors have greatly improved photo detectability compared to the conventional oxide phototransistor. Especially, these phototransistors are found to have sudden changes in electrical characteristics under the red light (wavelength of 635 nm) which was not absorbed by the conventional oxide phototransistor. These techniques are expected to be new approaches to improve the photo detectability of the oxide phototransistor up to the visible light region.


Speaker Bio:
Prof. Hyun Jae Kim has received his Ph.D. degree from Columbia University, USA in 1996. From 1996 to 2005, he has been a principal researcher in Samsung electronics. From 2004 to 2005, he also visited Ecole Polytechnique in France as a visiting professor. He has been a professor at the School of Electrical and Electronic Engineering, Yonsei University since 2005. He has been a program committee at Society for Information Display since 2005, and he has also been an Asian Program Committee Chair since 2013. He also served his duties at KIDS as a program vice chair for IMID, secretary, and etc. His current research interests are solution-processed materials and the devices; thin-film transistors, memories, solar cells, and biosensors.

Contact:
Cheryle Wills
Jacobs Hall, Room 2903
email: clwills@eng.ucsd.edu