发明名称 |
Reduced volume interconnect for three-dimensional chip stack |
摘要 |
A method of forming a reduced volume interconnect for a chip stack including multiple silicon layers, the method including: forming multiple conductive structures, each of at least a subset of the conductive structures having a volume of conductive material for a corresponding under bump metallurgy pad onto which the conductive structure is transferred that is configured such that a ratio of an unreflowed diameter of the conductive structure to a diameter of the corresponding pad is about one third-to-one or less; transferring the conductive structures to the silicon layers; stacking the silicon layers in a substantially vertical dimension such that each of the conductive structures on a given silicon layer is aligned with a corresponding electrical contact location on an underside of an adjacent silicon layer; and heating the interconnect so as to metallurgically bond multiple electrical contact locations of adjacent silicon layers. |
申请公布号 |
US9543273(B2) |
申请公布日期 |
2017.01.10 |
申请号 |
US201514599824 |
申请日期 |
2015.01.19 |
申请人 |
International Business Machines Corporation |
发明人 |
Gruber Peter A.;Sakuma Katsuyuki;Shih Da-Yuan |
分类号 |
H01L21/00;H01L25/065;H01L25/00;H01L23/00;H01L23/31;H01L21/56 |
主分类号 |
H01L21/00 |
代理机构 |
Otterstedt, Ellenbogen & Kammer, LLP |
代理人 |
Morris, Esq. Daniel P.;Otterstedt, Ellenbogen & Kammer, LLP |
主权项 |
1. A method of forming a reduced volume interconnect for a chip stack including a plurality of silicon layers, the method comprising:
forming a plurality of conductive structures, each of at least a subset of the conductive structures having a volume of conductive material for a corresponding under bump metallurgy (UBM) pad onto which the conductive structure is transferred that is configured such that a ratio of an unreflowed diameter of the conductive structure to a diameter of the corresponding pad is about one third-to-one or less; transferring the conductive structures to the silicon layers; stacking the silicon layers in a substantially vertical dimension such that each of the conductive structures on a given silicon layer is aligned with a corresponding electrical contact location on an underside of an adjacent silicon layer; and heating the interconnect so as to metallurgically bond multiple electrical contact locations of adjacent silicon layers in such a manner that at least a given one of the conductive structures between aligned electrical contact locations on corresponding adjacent silicon layers collapses to reduce an interconnect gap therebetween; wherein transferring the conductive structures to the silicon layers comprises transferring at least two of the plurality of conductive structures to a single corresponding UBM pad, an aggregate volume of conductive material forming the at least two conductive structures being substantially equal to a volume of a single conductive structure having a ratio of an unreflowed diameter of the single conductive structure to the diameter of the corresponding pad of about one third-to-one or less. |
地址 |
Armonk NY US |