Research And Realization On DI Readout Circuit For IRFPA Based On QWIP

Modern infrared(IR)focal plane arrays(FPA)technology has become a advanced comprehensive technologies,including IR material,optics,crygenics,solid-state micromachining technique,microelectronics,and so on.IRFPA plays an important role in military affairs,and can be widely applied in industry and civil fields. Infrared-focal-plane-array(IR FPA)is mainly made up of two parts:detector and readout-circuit(ROC). CMOS ROIC is becoming a main developing direction of ROIC.ROIC is one of core components in IRFPA.The performances of IRFPA,and even of IR system are directly affected by ROIC.Our country began developing CMOS ROIC in the nineties of the 20th century.And now we are still at starting stage.The performance of our ROIC is much lower than that of West developed countries.Now,it is very urgent to develop IRFPA technology of our own.Aiming at the above problems,the author has read many latest corresponding materials at home and abroad,and has got a general view of the state of arts of IR FPA. The topic decided to design one kind reading circuit, based on the QWIP(quantum well infrared photodetector) infrared focal-plane array, which can satisfy the QWIP array's characteristic request. To many key technical problems in CMOS ROIC design, and several readout circuit structures(DI,BDI (buffer direct input)structure),this author made deep and systemic analyses about the operational principle and circuit design, emulated many types of ROIC at different operational circumstances and technical conditions. And based on the general analysis and understanding of the state of arts of CMOS readout techniques for IR FPA,this author points out the strong points and weak points of the state of art of ROIC,and creatively improves several new types of CMOS readout techniques for IR FPA.In the artical, the comparison has carried on several typical CMOS reading circuit way, Then many theoreticals are analyzed and simulated on the DI reading-out circuit which used in this article.The circuit has a stable bias voltage, the better inhibition dark current and noise suppression,and the circuit is helpful actual ROIC design later. In the atical, the circuit and the IC layout were accomplished with the Cadence.then the testing work was carried out on the chip after the chip flow. the results show that this circuit is corresponded the initial design requirements.