Patent ID: 7737001

Claim:
A semiconductor device manufacturing method comprising the steps of: (a) providing a semiconductor wafer having a semiconductor substrate including a main surface, a reverse surface opposing to the main surface, and a wiring layer with a low dielectric constant layer and an interlayer insulating layer formed on the main surface of the semiconductor substrate; wherein the interlayer insulating layer is formed on the main surface of the semiconductor substrate, and wherein the low dielectric constant layer is formed on the interlayer insulating layer; (b) forming a modified region by irradiating a laser beam to the semiconductor wafer, wherein the modified region is formed by heating and melting an inside of the semiconductor wafer; and (c) after the step (b), dividing the semiconductor wafer into a plurality of semiconductor chips based on the modified region, wherein in the step (b), the laser beam is irradiated to the semiconductor wafer such that the modified region formed by irradiating the laser beam to the semiconductor wafer contacts with a part of the low dielectric constant layer, a part of the interlayer insulating layer and a part of the semiconductor substrate.