Monitoring the Quality of CCD Process by Microelectronic Test Patterns
Zhang Gang Lin Yingxin Wang Jin Wang RenwuThe Engineer of Ncrth China Photoelectroaics Research Institute. Assistant Researcher of Shanghai Institute of Technical Phyics.
According to the characteristics and requirement of Si-CCD device, a system of microelectronic test patterns to monitor the quality of Si-CCD process has been designed and applied to actual Si-CCD process. We focused on researching the storage time Tc and the surface state density Nss while analysing other parameters. This paper suggests that in the process the decrease of the storage time is due to the induced dislocation which has resulted from intergranular stress on the polycrystalline silicon in second gird oxide growth, and that surface state density mainly depends on grid oxide growth and annealing, and is not obviously related to the sequence of process. The whole experiment demonstrates that monitoring the quality of CCD process and analysing failure of the device by microelectronic test patterns is practical and reliable.