SEMICONDUCTOR DEVICE MANUFACTURING METHOD AND SEMICONDUCTOR DEVICE

摘要

The invention improves performance of a solid-state image sensor in which each of the pixels arranged in a pixel array part includes a microlens and plural photodiodes. The locations of the opposing sides between the photodiodes arranged side by side in each pixel are self-alignedly defined by a gate pattern. The location over wiring where the microlens is to be formed is checked and determined using as a superposition mark a check pattern of the same layer as a gate layer.

主权项

1. A semiconductor device manufacturing method for manufacturing a semiconductor device having a solid-state image sensor provided with a pixel including a first photodiode, a second photodiode, and a lens, the method comprising the steps of:
(a) preparing a substrate having a first area and a second area over an upper surface thereof; (b) forming a well region of a first conductivity type over an upper surface of the substrate in the first area; (c) forming a first gate layer over the substrate in the first area and a second gate layer over the substrate in the second area; (d) forming the first photodiode and the second photodiode to be beside the first gate layer over the upper surface of the substrate in the first area by implanting impurities into the upper surface of the substrate in the first area using the first gate layer as a mask, the first photodiode and the second photodiode including a first semiconductor region of a second conductivity type different from the first conductivity type; (e) after the step (d), forming a wiring layer over the substrate; and (f) over the wiring layer, forming the lens in a location determined using the second gate layer as a reference, wherein, in the step (d), the first photodiode and the second photodiode are formed on both sides of the first gate layer, respectively, as seen in a plan view.