英语论文网

We have demonstrated a 40-inch diagonal, full color WXGAAMOLED TV. It was based on 代写留学生论文the technologies of amorphous silicon (a-Si) TFT backplane and white OLEDwith color filter. Despite of recent technology advancement enabling high color purity, large-sized AMOLED, a lot of problems to solve still exist to enter the large-sized display market. Here, Samsung will discuss how far the technologies need to go for the marketplace of large-sized display.

1. Introduction
AMOLED have gained considerable interest for flatpanel displays due to their demonstrated capacity in highbrightness, wide viewing angle, fast response time andlower manufacturing cost compared to AMLCD. Due to impressive performance, it attracts the manufacturer’s and consumer’s interest as a lucrative market segment of the display industry. However, in order to compete withAMLCD and PDP, the AMOLED should overcome a lot of hurdles in commercialization.

First of all, OLED is a current driven device. Hence, the active matrix needs a driver circuit with a least two thin-film transistors (TFTs) to control the driving current [1].Recently, hydrogenated amorphous silicon thin-film transistors (a-Sigh TFT) widely used in AMLCD process have been considered as the pixel elements of AMOLE because of the uniformity and fabrication process for large-size and low cost panels [2-4]. Unfortunately, since testability of a-Sigh is poor for a current driven device, the threshold voltage shift happens due to electrical stress overtime. Threshold voltage of driving TFTs tends to increase with operating time due to the electrical stress. It induces the pixel to get darker with operating time, which is the critical issue to solve.

Another issue for AMOLED TV is a patterning fooled to describe R/G/B pixels. Fine metal mask method that has been developed in OLED is hard to expand more than Gen-4 substrate application under the current technology. Hence so many approaches have been proposed to overcome it for large-sized OLED displays. Among the various technologies to date, we consider white OLEDemitter with color filter (CF) to be strong candidate for large-sized AMOLED TV architecture.

The additional key requirement for succeeding above architecture is an efficient and stable white emitter [5].Basically the performance of OLED devices is dependent on the properties of organic materials. For instance, the lifetime of small molecules for white display with a stack of red, green, and blue layers is not long enough for the competitive OLED display product. Especially, blue host and do pant system for the full color display shows very low performance with respect to the lifetime, CIE color coordinate, and efficiency. Also the efficiency for the low power consumption is a crucial factor in the material properties. In addition to an optimized white device, the white OLED must also be designed to have little or no perceptible color shift when viewed at an angle, and of course, an acceptable lifetime.

4. References
[1] A. Nathan et al., IEEE Journal of Selected Topics in Quantum Electronics, Vol. 10, No.1 (2004)
[2] J. J. Lie et al, SID’03 Digest, p.14 (2003).
[3] T. Tsumimura et al, SID’03 Digest, p.6 (2003).
[4] T. Shirasaki et al., SID’04 Digest, p.1516 (2004).
[5] Hat war et al, Proc. EL Toronto (2004).
[6] J. Jung et al, SID’05 Digest, p. 153本论文由英语论文网提供整理，提供论文代写，英语论文代写，代写论文，代写英语论文，代写留学生论文，代写英文论文，留学生论文代写相关核心关键词搜索。