Degradation behavior and damage mechanisms of CCD image sensor with deep-UV laser radiation

• Published in: IEEE transactions on electron devices Vol. 51; no. 12; pp. 2229 - 2236
• Main Authors: Li, F.M., O, N., Nathan, A.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.12.2004; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: 157 nm; Applied sciences; Charge coupled image sensors; Charge transfer devices; charge-coupled devices (CCDs); Conductivity; deep-ultraviolet (DUV); Electronics; Exact sciences and technology; Excimer lasers; General equipment and techniques; image sensors; Imaging devices; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Interfaces; laser radiation effects; Lasers; Physics; Process controls; radiation damage; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing; Silicon materials/devices; Studies; ultraviolet radiation effects; Performance evaluation; deep- ultraviolet (DUV); Conversion rate; radiation damage; Industrial application; Charge coupled device; 157 nm; CCD image sensors; ultraviolet radiation effects; CCD camera; Imaging; Vacuum ultraviolet radiation; Optical characteristic; Dark current; Excimer lasers; Current density; Electrical characteristic; Damaging; Semiconductor insulator contact; Process control; Ultraviolet laser; Measurement sensor; Radiation source; F2 excimer lasers; charge-coupled devices (CCDs); Quantum yield; laser radiation effects; image sensors; Ultraviolet radiation; Laser beam
• ISSN: 0018-9383; 1557-9646
• DOI: 10.1109/TED.2004.839758

As the deep-ultraviolet (DUV) laser technology continues to mature, an increasing number of industrial applications is shifting to intense DUV radiation sources. This trend necessitates the development of DUV sensitive charge-coupled device (CCD) cameras to provide imaging capability for process control and inspection purposes. In this paper, we examine the effects of DUV laser radiation on CCD image sensor characteristics and the mechanisms responsible for DUV laser damage in CCDs. When samples of thinned front-illuminated linescan CCD sensors are exposed to F/sub 2/(/spl lambda/=157 nm) excimer laser radiation, fluctuation in the extrinsic quantum efficiency (QE) and a substantial upsurge in the dark current density are observed as a function of exposure dose. The visible QE, dark current, and charge conversion efficiency (CCE) are also permanently altered by the DUV irradiation. These instabilities can be attributed to a variety of UV-induced effects that modify the optical and electrical properties of the SiO/sub 2/ layer and Si-SiO/sub 2/ interface, resulting in temporary and permanent shifts in CCD performance. Optimization of the overlying oxide thickness and the Si-SiO/sub 2/ interface quality are necessary in order to realize CCD sensors with the desired performance, radiation tolerance and stability at DUV wavelengths.