SID Display Week 2023, Los Angeles, USA
May 22 - May 26, 2023 (Mon. - Fri.), Los Angeles Convention Center
An AMOLED Pixel Circuit Compensating for Variation of Sub-threshold
Swing and Threshold Voltage Based on Double Gate a-IGZO TFTs
SID Display Week 2023, Los Angeles, USA
May 22 - May 26, 2023 (Mon. - Fri.), Los Angeles Convention Center
An AMOLED Pixel Circuit Compensating for Variation of Sub-threshold
Swing and Threshold Voltage Based on Double Gate a-IGZO TFTs
Metamaterials 2022, Siena, Italy
September 12 - September 17, 2022 (Mon. - Sat.), Siena Univ.
Trans-Reflective Dual-Mode Terahertz Spatial Light Modulator Using Electrically Tunable Metasurface
Wonwoo Lee, and Hojin Lee
Abstract
Terahertz imaging systems have been extensively studied due to its high-resolution and non-destructive characteristics implementing the considerable potential for security inspection, bio-chemical material identification, and real-time imaging technologies. Despite remarkable progresses, conventional terahertz imaging systems require high power source, expensive detector, and complicate and time-consuming systems. In this regard, single-pixel imaging technique has been implemented into the terahertz range to realize compressive and real-time imaging. However, previous researches only allow the transmissive or reflective imaging technique owing to the passive or absorption type spatial light modulators (SLM). In this work, transmissionreflection dual-mode terahertz spatial light modulator is presented using electrically tunable metasurface based on ion-gel gating graphene metasurface. By applying differential driving voltage on the proposed SLM, differential respective object images could be successfully obtained simultaneously both for transmission and reflection mode exhibiting high correspondence with real objects.
IMID 2022, Pusan, Korea
August 23 - August 26, 2022 (Tue. - Fri.), Bexco
Monolithic Circuit Integrated with VOC Sensor Based on a-IGZO TFT
Eseudeo Yun, Yongchan Kim, Hanbin Choi, Do Hwan Kim, and Hojin Lee
Abstract
As volatile organic compound (VOCs) gases generated in industrial production lines is harmful to the human
body, study on detecting VOCs gases has attracted much interest. For detection of various VOCs, Amorphous
oxide semiconductors (AOS) have been highly researched to produce high-sensitivity chemoresistive-type VOCs
gas sensors. Especially, amorphous indium gallium zinc oxide (a-IGZO) thin film transistors (TFTs) are
considered the most promising candidate for gas sensors, thanks to their high field-effect mobility, low leakage
current, good uniformity, and superior electrical stability with the low-temperature process. However, a-IGZObased gas sensors reported so far still remain in an early stage such as for resistor-type sensor or a single TFT. In this talk, we proposed a monolithic sensor circuit with high sensitivity capable of amplifying the sensing
signal of the solution-processed a-IGZO sensor TFT.
IMID 2022, Pusan, Korea
August 23 - August 26, 2022 (Tue. - Fri.), Bexco
Ultra-High Resolution Organic Light-Emitting Diodes Based on Plasmonic Patterned Nanograting Array
Ryungyu Lee, Keun-Yeong Choi, and Hojin Lee
Abstract
Organic light-emitting diodes (OLEDs) have led to the rapid growth of the next-generation display technology
due to high luminance efficiency, vivid color, and high contrast ratio, thereby expanding their applications from
conventional mobile or TV displays to virtual reality (VR)/ augmented reality (AR) displays. For more effective
light extraction, implementing nanostructures onto metal electrode layer of OLEDs as a future display technology
has been demonstrated by use of excitation and out-coupling of the surface plasmon-polariton modes (SPPs).
In this work, we propose a high resolution OLEDs based on plasmonic patterned nanograting array (PNA) that
induces a plasmonic effect on OLEDs through the nano-patterned organic emission layer by applying E-beam
lithography on the fabrication process without deterioration of intrinsic physical/photoelectric properties of
organic layers.
IMID 2022, Pusan, Korea
August 23 - August 26, 2022 (Tue. - Fri.), Bexco
Novel AMOLED Pixel Circuit Compensating for Variations in Sub-threshold Swing and Threshold Voltage of a-IGZO Thin-Film Transistors
Hyunwoo Kim, Yongchan Kim, and Hojin Lee
Abstract
Amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors (TFTs) have been employed for the backplane
of AMOLED displays because of high carrier mobility, good uniformity, and low off currenet. However, it is
inevitable to have variations in threshold voltage (VTH) and sub-threshold swing (S.S.) due to bias-stress during
display operations as well as the fabrication deviations. The VTH shift can be attributed to charge trapping in gate
dielectric and interface states of semiconductor materials while the S.S. variation can cause a problem of leakage
current that increases power consumption. Therefore, a circuit-level compensation method for deviation is required. In this paper, we have proposed a novel a-IGZO TFT pixel circuit which can compensate for the VTH and S.S.
variation of the drive TFT.