Patent ID: 8110460
Filing Date: 2012-02-07
Classification: H01L

Abstract:
1. A method for producing stacked and self-aligned components on a substrate, comprising the following steps: providing a substrate made of monocrystalline silicon having one face enabling production of components, forming a stack of layers on the face of the substrate, the stack comprising a first sacrificial layer made of monocrystalline SiGe formed on the face of the substrate, a second sacrificial layer made of monocrystalline SiGe formed on the first sacrificial layer, a germanium concentration of the first sacrificial layer being between 30% and 100%, a germanium concentration of the second sacrificial layer being between 10% and 30%, the germanium concentration of the first sacrificial layer being at least 15% greater than the germanium concentration of the second sacrificial layer, and a superficial layer made of monocrystalline silicon enabling the production of the component and formed on the second sacrificial layer, said layers of the stack being formed so as to enable an access to at least one zone of the first sacrificial layer and to at least one zone of the second sacrificial layer, these zones being stacked, selective etching of said zone of the first sacrificial layer by a gaseous mixture comprising gaseous HCl conveyed by a carrier gas and at a temperature between 450° C. and 900° C., the second sacrificial layer and the superficial layer forming a bridge above an etched zone of the first sacrificial layer, depositing resin in the etched zone of the first sacrificial layer and on the superficial layer, the resin being a resin that transforms into dielectric material after annealing, implementing lithography of the resin deposited at the depositing step to leave remaining at least one zone of resin in the etched zone of the first sacrificial layer, in alignment with at least one zone of resin on the superficial layer, replacing resin eliminated during the lithography in the etched zone of the first sacrificial layer and on the superficial layer with a material for confining remaining resin, eliminating zones of the remaining resin in the etched zone of the first sacrificial layer and on the superficial layer to provide zones dedicated to the production of the components, forming elements of the components in the dedicated zones, and selective etching of said zone of the second sacrificial layer, the superficial layer forming a bridge above said etched zone of the second sacrificial layer.