Structure of a color sensor of a diode

#This application claims the priority benefit of Taiwan application serial no. 87104078, filed Mar. 19, 1998, the fall disclosure of which is incorporated herein by reference.

#1. Field of the Invention

#This invention relates in general to the structure and fabrication method of a diode color sensor, and more particularly to the structure of a type of Complementary Metal-Oxide-Semiconductor (CMOS) diode color sensor by using a black matrix layer.

#The invention can be more fully understood by reading the following detailed description of the preferred embodiments, with reference made to the accompanying drawings, wherein:

#FIG. 1 is a sectional view of a conventional color sensor of a CMOS diode;

#FIG. 2A is a sectional view of a color sensor of a CMOS diode according to a preferred embodiment of this invention; and

#Preferred embodiments of the present invention provide the structure of a CMOS diode color sensor as shown in FIG. 2A. A color sensor layer 22, which includes a number of color sensor areas for absorbing different color light, such as a color sensor 22a, a color sensor area 22b and a color sensor area 22c. All of 22a, 22b and 22c are formed on a substrate 20. Then, a black matrix film 24 preferably made of a kind of opaquely black pigment is formed over this color sensor layer 22, that is, over the color sensor areas 22a, 22b, and 22c. The black matrix film 24 is preferably formed by dispersed pigment method. It is characterized in this invention that this black matrix film 24 is preferably taken to be located around the interfaces between those color sensor areas 22a, 22b, and 22c and has a shape of matrix grid as viewed from the top so that the rectangular voids are matched to the color sensor areas leaving unshielded and therefore the interference between monochromatic lights is reduced. Then, a transparent planarization film 26 made of acrylic material is formed on a black matrix film 24. Then a color filter 28 is formed on this transparent planarization film 26 having a red filter R2, a green filter G2, and blue filter B2 by a way of, for example, electrolysis method, dye Method or dispersion pigment method. And then, a cover film 30 is formed on the top for the protection. In general, the incident light onto a diode color sensor includes different color light with different incident angles. This black matrix film 24 can reduce the interference between these monochromatic lights. When the incident light is filtered through the color filter 28 it will be filtered into red, green and blue light by color filters R2, G2, and B2 respectively and then will be absorbed and sensed by color sensor areas 22a, 22b, and 22c, respectively.

#Next, a top view of FIG. 2A is shown in FIG. 2B. As shown in FIG. 2B, this black matrix film 24 is placed at the color sensor layer 22 and under the color filter 28, which includes a red filter R2, a green filter G2, and a blue filter B2. As clearly seen in the FIG. 2B, the black matrix film 24 has a shape of matrix grid (dotted area) with the rectangular voids being arranged in an array of matrix matching to the color filter elements R2, G2, and B2 which are contained in the color filter, respectively.

#In the conclusions of above, the preferred embodiments of the present invention provide the structure and the fabrication method of a CMOS diode color and have characteristics as follows: