Surface Formation Laser Radar Chip Design And Production

Laser radar has a great many merits such as its high resolution in angle,range and speed,and therefore,it is widely used in civil and military fields.Compared to traditional intensity image of two-dimensional imaging laser radar,which does not accurately identify targets at the different distances,the range information helps discriminating objects,and so three-dimensional imaging laser radar to improve the recognition capability is effective.However,chip of laser radar is an important parts of radar system.Metal-Semiconductor-Metal(MSM) photodetectors have promising applications of optoelectronics integrated circuits(OEIC).This structure results in two important features.First,simplicity in processing and fabrication;Second,it convenient for large scale integration radar chip because of their planar structure.MSM-PD has the properties of high-speed,high-sensitivity,and it can be propitious to high-speed 3D imaging laser radar system.After considering the photo and electrical propertity of MSM-PD,used the theory of thermionic emission model of MSM,in this article.We carried out some research on radar chip as following.Firstly,the thermionic emission model of MSM photodetector are studied in detail,and the fundamental working mode of GaAs MSM photodetector are explained;Secondly,design the mask of the optical lithography;Thirdly,grow GaAs materials using the low pressure metal organic chemical vapor deposition(LP-MOCVD) equipment;Fourthly,fabricate the chip of laser radar by technique of optical lithography, 'lift-off' method,reactive ion eth,metal vaporize,encapsulation and so on;Fifthly,measure the responsibility,Ⅰ-Ⅴcharacteristic,frequency characteristic, and explained the gain of the photo-current.In the end,we fabricated the 32×32 pixels laser radar photodetector chip.As the 2V biasing,the responsibility is 6.45A/W,the dark-current is 18nA,the frequency response is 1.65GHz.