论文部分内容阅读
GaAs/AlGaAs多量子阱红外探测器是基于量子阱导带内子能带间或子能带到扩展态间的光电子跃迁对红外辐射的吸收特性而研制成的新型红外探测器.它具有响应速度快(皮秒量级)、量子效率高、波长和带宽可调、热稳定性好、抗辐射能力强等特点,有利于制成大面积焦平面列阵红外探测器.近年来为了充分利用GaAs/AlGaAs量子阱材料的特点和优势,研究和探索新结构新器件的工作一直不断,其中光伏和双色红外探测器具有重要价值.光伏型探测器与信号处理电路易于集成,结构简单,功耗小,工作温度也较高,因而有利于发展焦平面列阵技术;3～5μm和8～12μm两个波段是重要的大气传输窗口,能同时工作在此波段的双色器件在军事、民用上有着特殊应用前景.本文的工作就是试图在理论上提出一种集光伏双色于一体的量子阱红外探测器结构.1 器件设计理论最近,AT＆T Bell实验室Capasso小组证实,在量子阱层中,波函数的局域化也可以发生在大于势垒高度的连续态中.在主量子阱结构两旁的垒区中引入方势阱叠层,这些方势阱称作Bragg反射阱,由于Bragg方势阱宽度接近主量子阱连续态电子de Broglie波长的1/4,故反射相干作用可使主量子阱区的连续激发态密度集中于某些能量处,从而增加基态到这些准束缚态的跃迁振子强度,这对于实现器件光电吸收?
GaAs / AlGaAs multi-quantum well infrared detector is based on the quantum well conduction band within the sub-band or sub-band to the extended state of the photoelectron transition infrared radiation absorption characteristics developed and developed a new type of infrared detector with fast response ( Picosecond order of magnitude), high quantum efficiency, tunable wavelength and bandwidth, good thermal stability and strong anti-radiation ability, which is good for large-area focal plane array infrared detectors.In recent years, in order to make full use of GaAs / AlGaAs The characteristics and advantages of quantum well materials, research and exploration of new structures and new devices have been ongoing, of which photovoltaic and two-color infrared detector has important value.Photovoltaic detectors and signal processing circuits are easy to integrate, simple structure, low power consumption, work The temperature is also higher, which is conducive to the development of focal plane array technology; two bands of 3 ~ 5μm and 8 ~ 12μm are important atmospheric transmission windows. Two-color devices capable of working at the same time in this band have special application prospect in military and civilian applications The work in this paper is trying to put forward a theoretical structure of a quantum well infrared detector structure in one .1 device design theory recently, AT & T Bell experiment The Capasso team has demonstrated that in the quantum well layer the localization of the wavefunction can occur in a continuum that is greater than the height of the barrier.The square well layers are introduced into the barrier regions on either side of the main quantum well structure and these square wells Known as the Bragg reflection trap, since the Bragg square-well width is close to ¼ of the Broglie wavelength of the continuous-state electrons of the main quantum well, reflection-coherence can concentrate the continuous excited-state density of the main quantum well region at certain energies, Increase the ground state to these quasi-bound state transition oscillator strength, which for the device to achieve photoelectric absorption?