Integrated a‐Si TFT row driver circuits for high‐resolution applications

Abstract

A 12.1-in. tablet liquid-crystal-display (LCD) panel with integrated amorphous-silicon row driver circuits has been developed using a standard TFT process and Advanced Fringe-Field Switching (AFFS) technology. An XGA-resolution 768-stage shift-register circuit with two-phase clocks has been designed and fabricated. The circuit parameters were optimized in order to obtain a highly reliable a-Si row-driver-circuit structure. Thermal Humidity Operation (THO) test results at 50°C and 80% humidity during 500 hours of operation shows that the fabricated panel is reliable during long-term operation and any abnormal display phenomenon was not observed at 0°C.

Flexible TFT Circuit Analyzer Considering Process Variation, Aging, and Bending Effects

“…As a-Si TFT technology advances, not only pixel circuits but also large-scale analog circuits have been designed, for instance, shift register for gate driver [11], differential amplifier [13], embedded level shifter [14], and operational amplifier [15]. Examples of digital circuits include a pass-transistor multiplexer [16], an integrated row driver for high-resolution applications [17], an asynchronous finite impulse response filter [18], and pseudo-CMOS digital logic gates [19].…”

P.6: An Integrated a‐Si:H Gate Driver Circuit Design for Large‐sized TFT‐ LCD Applications

“…Hydrogenated amorphous silicon (a-Si:H) thin-film transistor (TFT) technology has become the main stream of large-sized active matrix flat-panel displays (FPD) due to the lower process temperature, simpler fabrication process, and better uniformity than the laser-annealed poly-Si TFT [1]- [11]. Moreover, integrated circuits on glass have attracted much attention owing to the advantages such as compactness, mechanical reliability, and the elimination of the external driver ICs which result in overall cost reduction [1]- [9].…”

“…Moreover, integrated circuits on glass have attracted much attention owing to the advantages such as compactness, mechanical reliability, and the elimination of the external driver ICs which result in overall cost reduction [1]- [9]. Consequently, a-Si:H gate driver circuits are widely used in large-sized displays nowadays.…”

“…Therefore, reducing V TH shift of the a-Si:H TFT is significant to an a-Si:H gate driver circuit design. Kim et al [1] proposed an a-Si:H S-R latch gate driver circuit having dcbiased pull-down TFT to stabilize the row line. Despite that the gate -source voltage (V GS ) is reduced to improve the V TH shift of the pull-down TFT, the dc-biased pull-down TFT may still degraded seriously under dc stress and shorten the life time of the circuit.…”

P‐27: Anomalous Increased Drain Current Characteristics of a‐Si:H TFTs with Long Channel Width

“…In recent years, amorphous-silicon thin film transistor (a-Si TFT) technology has been actively studied in order to expand its application areas into gate driver circuits [1][2][3], level shifters [4], and backplanes for AM-OLEDs [5]. Despite great effort, low field effect mobility of less than 1 cm 2 /V-sec for a-Si TFTs [6] is one of main obstacles for the broad commercialization of such applications.…”