用于空间光调制器光敏层的a—Si：H　pin二极管的研制

STUDY OF PREPARATION AND CHARACTERISTICS OF A-SI: H PIN DIODE FOR OASLM'S PHOTOSENSOR

报道了用于光寻址快速空间光调制器光敏层的氢化非晶硅ｐｉｎ光敏二极管的设计、制备及光电特性的研究，制得了符合光敏层要求的ｐｉｎ二极管。

We have in detailinvestigated the design, preparation and characterisitics of hydrogenated amorphous silicon (a-Si:H) pin photodiode used as photosensors in the highspeed optically addressed spatial light modulators (OASLM). The a Si:H pin photodiode is deposited on ITO/glass substrate at 250℃ by r. f. PECVD with the following reaction parameters: The concentration of the hydrogensediluted source gases SiH4, B2H6 and PH3 is 10%, 1 % and 0. 1%, respectively. The flow rate of SiH4 keeps 40 seem. For the p-layer or the n-layer, the doping gases B2H6 or PH3 are added in with the flow rate 4sccm. The thickness of the three layers is dp= 250A, di= 5000A, dn= 200A. The reacting pressure is 31. SPa and r. f. power 20W. We measured the I-V characteristics of the pin photodiode and found that Voc and Jsc increase almost linearly with the increase of the illumination intensity. The photodiode has a good response to the load resistance RL and the frequency f of the applied sinusoid voltage when RL<20kfl and fM8kHz. FrDm the above results, we demonstrate the pin photodiode is in good agreement with the requirement of OASLM.