Patent ID: 7449359

Claim:
A method of fabricating a CMOS image sensor, comprising: forming a plurality of photodiodes on a semiconductor substrate; alternately forming first insulating interlayers and first metal lines on a plurality of the photodiodes to thereby form the first insulating interlayer on the first metal line; forming a plurality of inner microlenses on the first insulating interlayer; alternately forming second insulating interlayers and second metal lines on a plurality of the inner microlenses to thereby form the second insulating interlayer on the second metal line; forming a device protecting layer on the second insulating interlayer; and forming a plurality of microlenses on the device protecting layer; wherein forming a plurality of inner microlenses comprises: attaching a silicon layer on the first insulating layer wherein oxide layers are coated on top and bottom surfaces of the silicon layer, respectively; forming a photoresist pattern on the silicon layer to expose an area corresponding to a plurality of the photodiodes; forming concave recesses by wet etching performed on the silicon layer using the photoresist pattern as a mask; and forming a nitride layer on the semiconductor substrate including the concave recesses; wherein forming concave recesses comprises: generating an inverse triangle type profile by performing the wet etching on the silicon layer; removing an oxide layer from a top surface of the silicon layer; and rounding the inverse triangle type profile by chemical dry etching to form each of the concave recesses.