SEMICONDUCTOR AND METAL ALLOY INTERCONNECTIONS FOR A 3D CIRCUIT

摘要

Fabrication of an integrated circuit comprising:
at least one first transistor made at least partially in a first semiconducting layer,at least one second transistor made at least partially in a second semiconducting layer formed above the first semiconducting layer,an insulating layer formed between the first transistor and the second transistor, one or several connection elements passing through the insulating layer between the first and the second transistor,at least one connection element being connected to the first and/or the second transistor and being based on a metal—semiconductor alloy.

主权项

1. Method for making one or several connection elements for an integrated circuit with superposed transistor levels, including:
a) fabrication of one or several openings (6) passing through a stack comprising at least one insulating layer (5) above a first transistor (T11) on a given level (N1), the first transistor being provided with a channel region located in a first semiconducting layer, then b) filling of the opening(s) (6) with a semiconducting material (8) so as to form one or several elements (9) based on a semiconducting material passing through the insulating layer (5), c) formation of the second semiconducting layer (22) on the stack, the second semiconducting layer comprising a channel region of a second transistor on another level (N2) higher than the given level (N1), then d) formation of at least one access well (46) to at least one element (9) among the one or several elements (9) based on a semiconducting material (8) passing through the insulating layer (5), e) deposition of a metallic material (48) in the access well (46) and apply a thermal annealing so as to form a alloy (58) based on metal and semiconductor starting from said semiconducting material (8) and said metallic material (48), so as to transform said element (9) based on a semi-conducting material (8) into an element based on an alloy (58) of metal and semiconductor passing through the insulating layer (5).