基于锌扩散的InGaAs/InP平面型红外探测器快速热退火研究

Study of Zinc-diffused InGaAs/InP planar infrared detector processed with rapid thermal annealing

系统研究了快速热退火对锌扩散的In_(0.53)Ga_(0.47)As/InP PIN探测器的影响。利用电化学电容电压和二次离子质谱技术分析了退火前后Zn和净受主的浓度分布,结果表明退火过程会影响杂质浓度,但不影响扩散深度。制备了不同退火条件的In_(0.53)Ga_(0.47)As/InP PIN探测器。器件测试反映,未退火的探测器在260~300K具有更低的器件电容和更高的激活能。通过暗电流成分拟合对器件暗电流机制进行分析,未退火器件表现出更低的肖克利-里德-霍尔产生复合电流和扩散电流,因而室温下未退火器件具有更高的峰值探测率。为了制备高性能低掺杂吸收层结构的平面型InGaAs探测器,快速热退火是不必要的工艺。

The function of rapid thermal annealing on zinc-diffused In_(0.53)Ga_(0.47)As/InP PIN detector was systemical⁃ly studied.By using electrochemical capacitance-voltage and secondary ion mass spectroscopy techniques,Zn and net acceptor concentration profiles were investigated,indicating that the annealing process would affect the dopant concentration but not affect the diffusion depth.In_(0.53)Ga_(0.47)As/InP PIN detectors under different annealing conditions were fabricated,the results showed that the detector without annealing process outperformed in terms of lower device capacitance and higher activation energy from 260 to 300K.By analyzing the mechanism of dark current,the unannealed sample exhibited lower Shockley-Read-Hall generation-recombination and diffusion cur⁃rents,explaining the higher peak detectivity at room temperature.Therefore,for the purpose of fabricating highperformance planar InGaAs detectors with low-doped absorption layer,annealing process is inadvisable.