Patent ID: 8231797
Filing Date: 2012-07-31
Classification: B81B,B81C,H01L,Y10T

Abstract:
1. A process for producing at least one air gap in a microstructure, the process comprising: a) providing a microstructure comprising at least one gap filled with a sacrificial material, wherein the gap is coated with an impermeable membrane, and wherein the impermeable membrane is rendered permeable by the action of a chemical etchant that is capable of degrading the sacrificial material, the chemical etchant comprising hydrofluoric acid or ammonium fluoride, or both; b) contacting the microstructure with the chemical etchant to make the impermeable membrane permeable and to allow the chemical etchant to diffuse through the permeable membrane so as to degrade the sacrificial material; and c) removing the chemical etchant from the microstructure, thereby obtaining the at least one air gap closed by the permeable membrane.