Title :
Drastically reduced dark current by pulse-time-modulated plasma for precise micro lens fabrication in highly sensitive CCD image sensor
Author :
Ishikawa, Y. ; Okigawa, M. ; Ichihashi, Y. ; Samukawa, S.
Author_Institution :
Inst. of Fluid Sci., Tohoku Univ., Sendai, Japan
Abstract :
Highly sensitive charge coupled device image sensors (CCD) have some serious problems such as increased dark current and interface states induced by the plasma etching processes. Especially, UV photon (200 nm to 300 nm) irradiation generates this damage. To solve this problem, we investigated optimum fluorocarbon gas chemistries and the effect of pulse-time-modulated (TM) plasma. We found that the dark current in CCDs was drastically reduced by carefully selecting gas chemistries and using TM plasma.
Keywords :
CCD image sensors; dark conductivity; interface states; microlenses; sputter etching; 200 to 300 nm; CCD image sensor; UV photon irradiation; charge coupled device image sensors; dark current reduction; interface states; micro lens fabrication; optimum fluorocarbon gas chemistries; pulse-time-modulated plasma etching; Charge coupled devices; Charge-coupled image sensors; Dark current; Fabrication; Image sensors; Interface states; Lenses; Plasma applications; Plasma chemistry; Plasma devices;
Conference_Titel :
Electron Devices Meeting, 2003. IEDM '03 Technical Digest. IEEE International
Conference_Location :
Washington, DC, USA
Print_ISBN :
0-7803-7872-5
DOI :
10.1109/IEDM.2003.1269306
