InGaAs焦平面探测器电串音性能研究

发布时间：2018-11-03 13:14

【摘要】：由In Ga As材料制备的短波红外探测器因其具有成本低、灵敏度高、可靠性高等特点,被广泛应用于工业、医疗和军事领域。近些年,由于材料生长和制备工艺的快速发展,各个领域对In Ga As焦平面阵列(FPA)的性能要求和需求越来越高。串音是影响焦平面阵列的成像性能的关键性因素,因此,In Ga As焦平面阵列的串音研究越来越受到人们关注。在本文的前半部分,我们首先系统地介绍了在模拟中用到的理论模型公式,我们在模拟中使用了泊松方程、载流子连续性方程、传输方程和产生-复合理论模型等经典的公式模型。然后,为了验证理论模型的合理性,我们模拟了In Ga As焦平面阵列的量子效率。在得到了量子效率正确结果的基础上,我们分析了暗电流与探测器结构、吸收层厚度、掺杂浓度的变化关系,定量地给出了In0.53Ga0.47As/In P PIN探测器的p-i结的耗尽层厚度值和n-i结的耗尽层厚度值,以及两者的电势分布情况。结果表明:平面结构的暗电流小于台面结构;在我们设计的结构下,在吸收层厚度小于1.5?m时,暗电流随着吸收层厚度的增加而增大,而当吸收层厚度大于1.5?m时,暗电流将趋于稳定,不再变动;In Ga As探测器的暗电流在吸收层低掺杂时,随着掺杂浓度的增大而减小;p-i结的耗尽层的宽度和分压能力比n-i结的耗尽层要大,并得到结论:在进行In0.53Ga0.47As/In P PIN探测器的理论分析时,n-i结相对于p-i结可以忽略。在本文的后半部分,我们进一步地,定量计算了In0.53Ga0.47As/In P探测器焦平面阵列的电串音与光波波长、入射方向和台面的刻蚀深度的变化关系。结果显示:台面结构器件的电串音抑制性能比平面结构的要好;由于材料吸收深度和异质结耗尽层宽度的影响,短波长入射光的电串音比长波长要小,正照射光的串音比背照射光要小;此外,当台面结构的刻蚀深度穿透吸收层时,其电串扰几乎完全被抑制。研究结果提出了相应的In Ga As FPA的低串音设计。除了以上内容,本文还对Vis-SWIR In Ga As探测器的量子效率和上海技术物理研究所的两个测量串音的实验进行了模拟。
[Abstract]:The short-wave infrared detectors prepared from In Ga As materials have been widely used in industrial, medical and military fields because of their low cost, high sensitivity and high reliability. In recent years, due to the rapid development of material growth and preparation technology, the performance requirements and requirements of In Ga As focal plane array (FPA) are becoming higher and higher in various fields. Crosstalk is a key factor affecting the imaging performance of focal plane arrays (FPAs), so the crosstalk of, In Ga As focal plane arrays (FPAs) has attracted more and more attention. In the first half of this paper, we first systematically introduce the theoretical model formulas used in the simulation, we use the Poisson equation, the carrier continuity equation, Classical formula models such as transmission equation and generation-composite theory model. Then, in order to verify the rationality of the theoretical model, we simulate the quantum efficiency of In Ga As focal plane arrays. Based on the correct results of quantum efficiency, we analyze the relationship between the dark current and the structure of the detector, the thickness of the absorption layer, and the doping concentration. The depletion layer thickness of p-i junction and the depletion layer thickness of n-i junction of In0.53Ga0.47As/In P PIN detector are quantitatively given, as well as their potential distribution. The results show that the dark current of planar structure is smaller than that of Mesa structure. When the thickness of the absorption layer is less than 1.5 m, the dark current increases with the increase of the thickness of the absorption layer, but when the thickness of the absorption layer is greater than 1.5 m, the dark current will be stable and will not change. When the absorption layer is low, the dark current of In Ga As detector decreases with the increase of doping concentration. The depletion layer width and partial pressure capacity of p-i junction are larger than that of n-i junction. It is concluded that the n-i junction can be neglected relative to p-i junction in the theoretical analysis of the In0.53Ga0.47As/In P PIN detector. In the second half of this paper, we further quantitatively calculate the relationship between electric crosstalk and wavelength, incident direction and etching depth of In0.53Ga0.47As/In P detector focal plane array. The results show that the crosstalk suppression performance of Mesa structure is better than that of planar structure. Due to the influence of material absorption depth and heterojunction depletion layer width, the electric crosstalk of short wavelength incident light is smaller than that of long wavelength, and the crosstalk of positive beam is smaller than that of backlit light. In addition, when the etching depth of the Mesa structure penetrates the absorption layer, its crosstalk is almost completely suppressed. The results show that the corresponding low crosstalk design of In Ga As FPA is proposed. In addition to the above, the quantum efficiency of Vis-SWIR In Ga As detector and two experiments of measuring crosstalk in Shanghai Institute of Technical Physics are simulated.
【学位授予单位】：上海交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN215

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