Design And Implementation Of Process Control Monitor Unit For CCD Image Sensor

Charge Coupled Device(CCD)image sensor,as one of the mainstream imaging devices,is mainly a kind of micro high-end chip that turns photoelectric signals into current and voltage signals,and then amplifies them through an amplifier to display the target object.CCD is widely used in civil applications,such as home card camera,mobile phone camera,traffic recorder,property security,etc.In military,such as remote positioning system,infrared remote sensing system,stealth target detection and so on.CCD is also particularly used in modern weapons and equipment,especially in satellites,spacecraft,low light night vision,missile cruise.It can be said that CCD is the eyes on weapons equipment,can observe the whereabouts and trajectory of the other side at any time,is a very core chip on modern weapons.With the development of high technology in recent years,the process of localization of CCD is also accelerating the development,and the trend of solving the bottleneck to achieve autonomous control is more and more obvious.The quality of CCD image sensor is directly related to the stability and reliability of weapons and equipment.Therefore,the performance and stability of CCD devices will be affected if any problems occur in the process of CCD chips.If the process control is not stable,the defects produced in the manufacturing process will directly lead to the failure of CCD devices.Process Control Monitor(PCM)is a process control technology that comprehensively reflects the process status of the production line.In order to avoid the failure of the produced CCD image sensor,a stable and reliable PCM monitoring unit is designed on the wafer for process control and monitoring in the early stage of CCD development.It is very necessary to accurately find the abnormal conditions in the process of chip manufacturing for the monitoring and improvement of the process state of CCD image sensor.In this thesis,the PCM technology of backlight CCD,multispectral CCD image sensor and other chips is studied.The hardware of PCM mainly includes: controller terminal module,test instrument platform,test probe,probe station and wafer bearing station system.Take in mature is the main technical means of CCD process line in the process of the upper piece,wafer in the margin to join the PCM structural unit,access to technology in the process of chip square resistance and contact resistance,MOS tube open voltage,the channel potential,alignment accuracy,such as monitoring data,and to handle a large number of test data for analysis to find the best reference for process control criterion,To realize the real-time monitoring of the process status in chip fabrication.In this paper,according to the actual situation of CCD process line running in 44 Institute of CETC combined with the general design method of integrated circuit manufacturing,a process control and monitoring unit suitable for 6-inch CCD chip production line is designed.The PCM technology has been successfully used in the CCD process line,and has played a key role in improving the yield of the CCD image sensor.The yield has increased from 70% to 85%.At the same time for CCD new device development,new process development,device failure analysis,process problem positioning,and so on,laid a solid foundation for monitoring data analysis.