Method for manufacturing semiconductor device
First Claim
1. A method for manufacturing a semiconductor device, in which an active layer is located on a supporting substrate with an insulating intermediate layer therebetween and a movable unit included in the active layer moves in relation to the supporting substrate in response to a force applied to the movable unit, wherein the force is correlated to a dynamic quantity to be measured by the device, the method comprising steps of:
- forming an SOI substrate that includes a semiconductor substrate, an insulating layer, and a semiconductor layer such that the insulating layer is located between the semiconductor layer and the semiconductor substrate;
dry etching the semiconductor layer to form a trench that extends through the semiconductor layer to the insulating layer, wherein the dry etching is performed with a charge prevented from building up on a surface of the insulating layer that is exposed during the dry etching in order to prevent notching;
dry etching a sidewall defining the trench at a portion adjacent to a bottom of the trench to form a movable unit, wherein the later dry etching is performed with a charge building up on the surface of the insulating layer such that etching ions strike to etch the portion of the sidewall.
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Accused Products
Abstract
A method for manufacturing a semiconductor device having a movable unit includes a step of forming an SOI substrate that includes a semiconductor substrate, an insulating layer, and a semiconductor layer such that the insulating layer is located between the semiconductor layer and the semiconductor substrate. The method further includes a step of dry etching the semiconductor layer to form a trench with a charge prevented from building up on a surface of the insulating layer that is exposed at a bottom of the trench during the dry etching. The method further includes a step of dry etching a sidewall defining the trench at a portion adjacent to the bottom of the trench to form the movable unit. The later dry etching is performed with a charge building up on the surface of the insulating layer such that etching ions strike to etch the portion of the sidewall.
19 Citations
9 Claims
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1. A method for manufacturing a semiconductor device, in which an active layer is located on a supporting substrate with an insulating intermediate layer therebetween and a movable unit included in the active layer moves in relation to the supporting substrate in response to a force applied to the movable unit, wherein the force is correlated to a dynamic quantity to be measured by the device, the method comprising steps of:
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forming an SOI substrate that includes a semiconductor substrate, an insulating layer, and a semiconductor layer such that the insulating layer is located between the semiconductor layer and the semiconductor substrate;
dry etching the semiconductor layer to form a trench that extends through the semiconductor layer to the insulating layer, wherein the dry etching is performed with a charge prevented from building up on a surface of the insulating layer that is exposed during the dry etching in order to prevent notching;
dry etching a sidewall defining the trench at a portion adjacent to a bottom of the trench to form a movable unit, wherein the later dry etching is performed with a charge building up on the surface of the insulating layer such that etching ions strike to etch the portion of the sidewall. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
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Specification