Patent ID: 11961740
Assignee: SHANGHAI HUALI INTEGRATED CIRCUIT CORPORATION
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A method for manufacturing semiconductor devices, wherein the semiconductor devices comprise gate dielectric layers at different thicknesses, the method comprising:
providing a semiconductor substrate for the semiconductor devices, wherein the semiconductor devices operate at different voltages associated with the gate dielectric layers at different thicknesses, wherein a thinner gate dielectric layer results in a lower operating voltage, wherein a gate dielectric layer at a thickness other than a minimum thickness is fabricated by following steps:
step 1: forming a first mask layer on a top surface of the semiconductor substrate;
step 2: patterning a region for one of the semiconductor devices and removing the first mask layer in the region to form a first opening, wherein said one of the semiconductor devices is configured to have a gate dielectric layer at a desired thickness;
step 3: forming a second groove at a bottom of the first opening by etching, wherein a depth of the second groove is configured to be the desired thickness of the gate dielectric layer of said semiconductor device;
step 4: filling the second groove and the first opening with a second material layer which relates to said gate dielectric layer;
step 5: forming said gate dielectric layer by etching back the second material layer, wherein a top surface of the second material layer is flush with a top surface of the semiconductor substrate;
step 6: removing a remaining portion of the first mask layer; and
repeating the steps 1 to 6 to form the gate dielectric layers of different thicknesses, wherein top surfaces of the gate dielectric layers of different thicknesses are configured to be at a same level.