Method of forming vias
First Claim
1. A method of forming a via in a semiconductor integrated circuit, comprising the steps of:
- forming a conductive structure over portions of an underlying region;
forming a conformal oxide layer over the conductive structure and the underlying region;
forming a planarizing oxide layer over the conformal oxide layer;
etching back the planarizing oxide layer to expose a portion of the conformal oxide layer over the conductive structure;
forming a metal oxide layer over the planarizing oxide layer and the exposed portion of the conformal oxide layer;
forming and patterning a resist layer over the metal oxide layer to define a selected via region;
etching the metal oxide layer to remove it from the selected via region, wherein the metal oxide etch is performed so as to selectively etch the metal oxide layer over the underlying conformal oxide layer;
etching the conformal oxide layer to remove it from the selected via region, wherein the conformal oxide etch is performed so as to selectively etch the conformal oxide layer over the metal oxide layer;
removing the resist layer; and
forming an upper interconnect structure over the metal oxide layer and extending into the via to contact the conductive structure.
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Accused Products
Abstract
A method is provided for forming a contact opening or via of a semiconductor integrated circuit, and an integrated circuit formed according to the same. A first metal region is formed over an underlying region. A first insulating layer is formed over the integrated circuit. A second insulating layer is then formed over the first insulating layer. A portion of the second insulating layer is etched to expose a portion of the first insulating layer wherein the exposed first insulating layer and the remaining second insulating layer form a substantially planar surface. A metal oxide layer is formed over the exposed first insulating layer and the remaining second insulating layer. A photoresist layer is formed and patterned over the metal oxide layer. The metal oxide layer is then selectively etched to form a via exposing a portion of the first insulating layer. The first insulating layer in the via is then selectively etched to expose a portion of the first metal region. The photoresist layer is removed and a second metal layer is then formed over the metal oxide layer and in the via contacting the first metal region.
40 Citations
12 Claims
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1. A method of forming a via in a semiconductor integrated circuit, comprising the steps of:
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forming a conductive structure over portions of an underlying region; forming a conformal oxide layer over the conductive structure and the underlying region; forming a planarizing oxide layer over the conformal oxide layer; etching back the planarizing oxide layer to expose a portion of the conformal oxide layer over the conductive structure; forming a metal oxide layer over the planarizing oxide layer and the exposed portion of the conformal oxide layer; forming and patterning a resist layer over the metal oxide layer to define a selected via region; etching the metal oxide layer to remove it from the selected via region, wherein the metal oxide etch is performed so as to selectively etch the metal oxide layer over the underlying conformal oxide layer; etching the conformal oxide layer to remove it from the selected via region, wherein the conformal oxide etch is performed so as to selectively etch the conformal oxide layer over the metal oxide layer; removing the resist layer; and forming an upper interconnect structure over the metal oxide layer and extending into the via to contact the conductive structure. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
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Specification