Formation of protective coatings for color filters

#(1) Field of the Invention

#The present invention relates generally to the fabrication of color light detectors. More particularly, the present invention relates to the formation of protective coatings on filters used in color light detectors.

#(2) Description of Related Art

#FIGS. 1A-1E illustrates a cross-section of a color filter array structure at various stages of the fabrication process.

#FIGS. 2A-2E illustrate a cross-section of a color filter array structure at various stages of an alternative fabrication process. The illustrated structure which results uses a silation layer appropriate for protecting against surface damage in a detape process.

#FIG. 3 illustrates a cross-section of a device using a color filter.

#In the following description, a protective silation layer will be formed over color filters used in semiconductor light sensing devices. The silation layer will protect and reduce the probability of damage to the color filters. For example, by using a silation layer, the detaping processes in grind/gold deposition processes will damage fewer color filters. The formation of a polymer silation layer between CFA layers also reduces the need for reworking of previously deposited layers when a subsequent CFA layer is misprocessed. Finally, the use of the silation layer between adjacent color filters reduces bleeding of pigments or CFA polymer material between adjacent different colored filters. Reducing bleeding improves the color selectivity of each filter.

#In the accompanying description, certain details will be provided to facilitate understanding of the invention. For example, the specification will recite processing times as well as processing materials such as hexamethyl di-silizane. However, it is recognized that other silation materials may be used and different processing times may be appropriate. The included details are provided to facilitate understanding of the invention and should not be interpreted to limit the scope of the invention. Certain details, for example, describing the steps used to create a photo-detector will be omitted, because such details would obscure the invention and are already well understood by those of ordinary skill in the art.

#The advantages and uses of the present invention may be understood by examining simplified cross-sectional representations of the color filter and protective layer. FIG. 1 and FIG. 2 illustrates a simplified cross-sectional view of the color filter and protective layer or coating at various stages in processing. FIG. 1 shows a simplified cross-sectional representation of a filter and protective layer when using the protective layer to reduce bleeding of pigment between adjacent filters. The embodiment shown in FIG. 1 also minimize the probability of having to “rework” previously created filters when a misprocessing step occurs.