Patent ID: 7736840
Filing Date: 2010-06-15
Classification: H01L

Abstract:
1. A method of producing two superposed elements within an integrated electronic circuit formed by successive levels starting from a surface of a substrate of the circuit, the method comprising the following steps: a) forming at least a first circuit element in a first circuit level, said first element being reflective for the radiation of a lithography process; b) forming a first layer above the first circuit level, in a first region of the circuit that contains a first part of the first circuit element but not in a second region of the circuit that contains a second part of said first element, said first layer being suitable for attenuating the radiation reflected by the first circuit element; c) forming a second layer that is substantially transparent to said radiation so as to cover the circuit at least over said second region; d) depositing a lithography resist mask on the circuit; e) exposing the resist mask to a primary radiation flux corresponding to an amount of radiation below the development threshold of the resist mask and defined so that the amount of radiation corresponding to the sum of said primary flux and of a secondary flux, obtained by reflection of said primary flux on the second part of the first circuit element, is above the development threshold of the resist mask; f) developing the resist mask so as to remove the portions of resist that have been exposed to the amount of radiation above the development threshold and form at least one aperture; g) etching the first and second layers through the at least one aperture of the developed resist mask; and h) depositing a portion of a defined material so as to form a second circuit element in contact with at least the second part of the first circuit element wherein the second circuit element has at least one first side defined by an edge of said first layer, and at least one second side superimposed with a side of said first circuit element.