SEMICONDUCTOR STRUCTURE AND METHOD FOR MANUFACTURING THE SAME

摘要

A semiconductor structure is disclosed. The semiconductor structure comprises: a substrate (130), a support structure (131), a base region (100), a gate stack, a spacer (240), and a source/drain region, wherein the gate stack is located on the base region (100), and the base region (100) is supported on the substrate (130) by the support structure (131), wherein the sidewall cross-section of the support structure (131) is in a shape of a concave curve; an isolation structure (123) is formed beneath the edges on both sides of the base region (100), wherein a portion of the isolation structure (123) is connected to the substrate (130); a cavity (112) is formed between the isolation structure (123) and the support structure (131); and there exists a source/drain region at least on both sides of the base region (100) and the isolation structure (123). Accordingly, a method for manufacturing the semiconductor structure is also disclosed.

主权项

1. A method for manufacturing a semiconductor structure, comprising:
a) providing a substrate (130) on which a gate stack and a first spacer (240) surrounding the gate stack are formed; b) removing part of the substrate (130) located on both sides of the gate stack to form a device stack; c) forming a second spacer (260) on both sides of the device stack; d) using the device stack with a second spacer (260) as a mask to etch the substrate located on both sides of the device stack so as to form a recess (160) located on both sides of the device stack and a support structure (131) below the device stack, wherein by controlling the etching, the sidewall cross-section of the recess is protruded to be in a curve-shape just below the device stack; e) forming a first semiconductor layer (110) to fill the recess; f) removing part of the first semiconductor layer (110) located on both sides of the device stack and retaining the first semiconductor layer (110) having a certain thickness; g) in a partial region in a width direction of the device stack, removing the first semiconductor layer (110) located on both sides of the device stack so as to expose the substrate (130); h) in the partial region in the width direction of the device stack, forming an isolation structure (123) connected to the substrate below the second spacer (260) and the edges on both sides of the device stack; i) removing the remaining first semiconductor layer (110) to form a cavity (112) between the support structure (131) and the isolation structure (123); and j) removing the second spacer (260) and forming a source/drain region on both sides of the device stack.