AMOLED Panel Research Articles

Flexible AM OLED panel driven by bottom-contact OTFTs

Active matrix organic-light-emitting-diode (AM OLED) panels, driven by organic thin-film transistors (OTFT), have been successfully fabricated on a flexible plastic substrate. The pixel circuit consists of two bottom-contact pentacene OTFTs working as switching and driving transistors. The panel has 16 /spl times/ 16 pixels, each of which have an OLED using a phosphorescent material with an emission efficiency of 30 cd/A. A tantalum oxide (Ta/sub 2/O/sub 5/) film with a dielectric constant of 24, prepared by the anodization of Tantalum (Ta), was used as the gate insulator of the OTFTs. The passivation layer on the OTFTs was formed by a layer of silicon dioxide (SiO/sub 2/) and two layers of polyvinyl alcohol. Using OTFTs with a Ta/sub 2/O/sub 5/ gate insulator, the authors have realized a flexible active matrix OLED panel driven with a low voltage of -12 V.

38.4: 6-bit AMOLED with RGB Adjustable Gamma Compensation LTPS TFT Circuit

RGB adjustable gamma compensation circuit to choose one of the three different gamma characteristics for each color has been integrated by LTPS TFT for AMOLED. A timing controller to generate all timing signals for a 6-bit data driver and a scanning driver has also been integrated by the TFT on the AMOLED panel.

P-43: Single DAC Current Delivery System for Driving AMOLED Panel with Increased Pixel Uniformity

A Current sink data-driver with 54 outputs for AM-OLED, driven by a current-programmed method, has been demonstrated. This driver can sink constant current as low as 1 μA with 6-bit analog levels.

35.1: 2.5‐in. AMOLED with Integrated 6‐Bit Gamma Compensated Digital Data Driver

Abstract6‐bit gamma compensated digital data driver using LTPS TFTs was integrated in AMOLED panel. We have applied conventional register ladder D/A converter circuits with 9 points reference voltage for each color. We have obtained both good gray scale and good white balance by optimizing the reference voltage. DC/DC converter and serial to parallel converter have also been integrated by TFT. The number of pixels is 768 × 228 dots. The width of the data driver designed by 2micron rule is only 2.6mm.

P‐70: Active Matrix OLED Displays Using Simple Poly‐Si TFT Process

AbstractWe have suggested and developed a novel 6 photo‐mask process for the p‐channel poly‐Si thin film transistor TFT panel fabrication of active matrix organic light‐emitting diode AMOLED. By removing power line Vdd and bank photo process, we simplified the fabrication process from 8 to 6 mask steps. The p‐channel TFT fabricated by the 6 photo‐mask process had a field effect mobility of ∼80 cm2/Vsec, a sub‐threshold voltage swing of ∼0.3 V/dec., and a threshold voltage of ∼−2 V. Using the 6 photo‐mask process, we have successfully realized a 7‐inch WVGA 720×480 AMOLED panel, which is controlled by the voltage driving method.