Abstract
This letter presents a highly sensitive near-infrared (IR) a-Si:H phototransistor for touch sensor applications. The narrow bandgap of a-Si exhibits a wideband spectrum response from IR to ultraviolet region, where the IR bandpass filter layers allow the a-Si:H phototransistor to respond to the selective IR light uninterrupted by visible light. The time-resolved photoresponse and transfer I-V characteristics for the near-IR a-Si:H phototransistor as a function of power at 785-nm illumination allow the observation of fast photoresponse (τ ∼ 0.1 ps), high external quantum efficiency (7.52), and high photoresponse. A prototype unit pixel structure for touch sensors composed of amorphous Si-based switching/amplification/near-IR phototransistors and a storage capacitor, is proposed and designed. The overall results suggest that the near-IR a-Si:H phototransistor offers unique possibilities for user-friendly, low-cost, and large-area touch sensors, especially aimed at consumer applications and other areas of optoelectronics.
Original language | English |
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Article number | 6949127 |
Pages (from-to) | 41-43 |
Number of pages | 3 |
Journal | IEEE Electron Device Letters |
Volume | 36 |
Issue number | 1 |
DOIs | |
State | Published - 1 Jan 2015 |
Keywords
- IR sensor
- phototransistor
- touch sensor
- α-Si:H