Method for release of surface micromachined structures in an epitaxial reactor
First Claim
1. A method for manufacturing at least one micromechanical element, comprising:
- providing a substrate layer, a sacrificial layer, and a function layer, the sacrificial layer overlaying at least a first portion of the substrate layer, the function layer overlaying at least a second portion of the sacrificial layer;
etching the function layer to expose at least a portion of the sacrificial layer, the etching forming an outline of the at least one micromechanical element; and
removing at least a third portion of the sacrificial layer between the at least one micromechanical element and the substrate layer by exposing the third portion of the sacrificial layer to heated gaseous hydrogen.
1 Assignment
0 Petitions
Accused Products
Abstract
A method for releasing from underlying substrate material micromachined structures or devices without application of chemically aggressive substances or excessive forces. The method starts with the step of providing a partially formed device, comprising a substrate layer, a sacrificial layer deposited on the substrate, and a function layer deposited on the sacrificial layer and possibly exposed portions of the substrate layer and then etched to define micromechanical structures or devices therein. The etching process exposes the sacrificial layer underlying the removed function layer material. Next there are the steps of cleaning residues from the surface of the device, and then directing high-temperature hydrogen gas over the exposed surfaces of the sacrificial layer to convert the silicon dioxide to a gas, which is carried away from the device by the hydrogen gas. The release process is complete when all of the silicon dioxide sacrificial layer material underlying the micromachined structures or devices is removed.
-
Citations
40 Claims
-
1. A method for manufacturing at least one micromechanical element, comprising:
-
providing a substrate layer, a sacrificial layer, and a function layer, the sacrificial layer overlaying at least a first portion of the substrate layer, the function layer overlaying at least a second portion of the sacrificial layer;
etching the function layer to expose at least a portion of the sacrificial layer, the etching forming an outline of the at least one micromechanical element; and
removing at least a third portion of the sacrificial layer between the at least one micromechanical element and the substrate layer by exposing the third portion of the sacrificial layer to heated gaseous hydrogen. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21)
-
-
22. A device including micromechanical elements, comprising:
-
a substrate layer;
a sacrificial layer on at least a first portion of the substrate layer; and
a function layer on at least a second portion of the sacrificial layer;
wherein the function layer is released from the substrate layer by exposing the device to gaseous hydrogen. - View Dependent Claims (23, 24, 25, 26, 27, 28)
-
-
29. A method, comprising:
-
patterning a function layer, the function layer overlaying at least a first portion of a sacrificial layer, the patterning exposing at least a second portion of the sacrificial layer, the sacrificial layer including an oxide; and
etching selectively the oxide of the sacrificial layer by exposing a third portion of the sacrificial layer to heated gaseous hydrogen. - View Dependent Claims (30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40)
-
Specification