As注入长波碲镉汞红外探测器工艺研究

As Ion Implantation Technology for LWIR HgCdTe Infrared Detector

p-on-n结构的碲镉汞红外探测器具有长的少子寿命、低暗电流、高R;A值等优点,是高温器件、长波甚长波器件发展的重要器件结构。而国内还鲜有砷注入掺杂p-on-n长波HgCdTe探测器的相关报道,为了满足军事、航天等领域对高性能长波探测器迫切的应用需求,针对As离子注入的长波p-on-n碲镉汞红外探测器退火工艺技术进行研究。采用二次离子质谱(SIMS)仪分析注入及退火后As离子浓度分布情况,使用半导体参数测试仪表征pn结的I-V特性。研究结果表明,在富汞0.5 h 430℃+20 h 240℃条件下,实现As激活,成功制备As注入长波15μm 640×512的p-on-n碲镉汞红外焦平面器件,器件有效像元率大于99.7%。该研究对长波甚长波碲镉汞p-on-n焦平面器件的制备具有重要意义。

The p-on-n HgCdTe infrared detector has advantages of long minority carrier life,low dark current,high R;A product,and is an important device structure in the development of high-temperature detectors along with long wavelength infrared(LWIR)and very LWIR(VLWIR)detectors.However,there are few local reports on arsenic-implanted doped p-on-n long-wave HgCdTe detectors.To meet the urgent application requirements of high-performance long-wave detectors in the military and aerospace fields,studies have focused on long-wavelength p-on-n HgCdTe infrared detector annealing technology for As ion implantation.Secondary ion mass spectrometry(SIMS)was used to analyze the distribution of As ion concentration after implantation and annealing,and a semiconductor parameter tester was used to characterize the I-V characteristics of the pn junction.The results show that under mercury-rich conditions at 430℃for 0.5 h and at 240℃for 20 h,the As was activated.Further,the As implanted long-wavelength 15-μm 640×512 p-on-n HgCdTe infrared focal plane detector was successfully fabricated,and the operable pixel factor of the detector was greater than 99.7%.This research is of great significance for the fabrication of LWIR and VLWIR mercury cadmium telluride p-on-n focal plane detectors.