Study on the LTPS TFT Circuits For X-ray Active Matrix Sensor

• Main Authors: Ko-Ching Su, 蘇可青
• Other Authors: Jyh-Long Chen
• Format: Others
• Language: en_US
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/14529320742343423292

碩士 === 國立交通大學 === 光電工程系所 === 94 === The application of low-temperature poly-Si TFT circuits for the high resolution X-ray active matrix sensor is explored. The integration of poly-Si TFT circuit on the glass enables an easy connection for the sensor array with fine pixel pitch. A novel charge sensitive amplifier circuit employing poly-Si TFTs is proposed for the readout system of the active matrix sensor. It can considerably reduce the circuit’s sensitivity to unavoidable threshold voltage variations of the poly-Si TFTs. The TFT VTH mismatch which results in the offset voltage of the charge amplifier can also be depressed by the new circuit. However, the noise arisen from the VTH mismatch can be even larger than that from the VTH variation after compensation. For the higher bit digital X-ray image, it must be properly taken into consideration.