47.2: 2.8‐inch WQVGA Flexible AMOLED Using High Performance Low Temperature Polysilicon TFT on Plastic Substrates

Abstract

This paper reports a low-temperature polycrystalline silicon (LTPS) fabrication process on plastic substrate for a flexible AMOLED display. Characteristics of fabricated TFTs showed excellent performance with field effect mobility of 124.1 cm 2 /Vs, on/off ratio of >10 8 , subthreshold slope of 0.30V/dec, and threshold voltage of -2.03V. Internal scan drive circuits, 1:3 demux, and compensation circuits were successfully integrated on the backplane of a 166ppi 2.8" WQVGA flexible AMOLED panel.

Low‐Power Flexible Organic Light‐Emitting Diode Display Device

“…Such high temperature treatments give rise to damaged foldable OLED display including fl exible OLED display devices, composed of two individual OLED panels [ 17 , 18 ] that pretend to display a single unfolded shape, but with a LTPS backplane implemented on a glass substrate with small mechanical fl exibility compared to the fl exible LTPS backplane. [ 16 ] The glass substrate is thinned to 50 μ m by chemical mechanical polishing (CMP) and is subsequently integrated with two thick protecting layers ( ∼ 500 μ m) on each side to form a neutral plane. For future fl exible display technologies, the development of the present fl exible display device incorporating a fl exible backplane [ 16 ] on a plastic substrate is expected to revolutionize the implementation of fl exible displays.…”

“…[ 16 ] The glass substrate is thinned to 50 μ m by chemical mechanical polishing (CMP) and is subsequently integrated with two thick protecting layers ( ∼ 500 μ m) on each side to form a neutral plane. For future fl exible display technologies, the development of the present fl exible display device incorporating a fl exible backplane [ 16 ] on a plastic substrate is expected to revolutionize the implementation of fl exible displays. display requires that a fl exible backplane that contains driving/ switching thin-fi lm transistors (TFTs) and capacitor must be integrated with the fl exible display devices suggested here.…”

“…display requires that a fl exible backplane that contains driving/ switching thin-fi lm transistors (TFTs) and capacitor must be integrated with the fl exible display devices suggested here. To minimize the mechanical stress, a fl exible backplane has been manufactured with supporting plastic layers, where the neutral plane [13][14][15][16] is defi ned as strain free zones under both inward and outward bending as shown in Figure 6 a. Importantly, recent research experimentally reported that TFTs and electrical devices placed on a neutral plane fabricated on a plastic substrate (polyimide) achieved a stable performance under 20 000 times tensile and compressive bending down to radii of 3 mm.…”

Field Plate Optimization in Low-Power High-Gain Source-Gated Transistors

“…Polysilicon technology has reached a maturity which enables reliable fabrication of high performance large area circuits [5,6], however, intrinsic to the polycrystalline nature of the material is the problem of device-to-device variations in drain current [7]. Additionally, the high carrier mobility coupled with the body of the transistor being electrically floating lead to the deleterious "kink effect" [8], also seen in silicon-on-insulator (SOI) devices [9].…”

Electrostatic Simulation Methodology for Capacitive Touch-Screen Panels

“…Significant progress has been made in achieving a flexible TSP design [16][17][18], a foldable/seamless TSP integrated display [19][20] and a robust rollable display [21].…”