使CCD基线平整的高频等离子退火工艺

实验证实,由Si-SiO_2-多晶硅之间的应力失配在外力作用下所引起的大量电子陷阱是导致CCD基线弯曲的根源。我们采用O_2+CF_4作为工作气体的高频等离子退火工艺,开发了CCD基线平整工艺,有效地消除了这些陷阱,从而使基线平整;并使转移频率得到改善。实验进一步证实:导致CCD基线弯曲的陷阱是一种深能级陷阱。

High Frequency Plasma Annealing for Smoothing the Reference Linne of a CCD

Experiments show that large number of electron traps induced by the unfit stress on Si-SiO2-polysilicon interface at external forces are responsible for fluctuations of the CCD reference line. Using O2 + CF4 as processing gas, a process of high frequency plasma annealing has been developed, effectively removing the electron traps and thus making the line smooth, and also improving the transition frequency. It is also demonstrated that the electron traps inducing the fluctuations of the CCD reference line are traps of deep energy level.