公开(公告)号：US12091310B2

公开(公告)日：2024-09-17

申请号：US17331762

申请日：2021-05-27

Applicant: TallannQuest LLC

Inventor： David A. Grant ,  Abhijeet Ghoshal

IPC: B81B3/00 ,  B81C1/00 ,  H02N10/00

CPC classification number: B81B3/0072 ,  B81C1/00666 ,  H02N10/00 ,  B81B2201/031 ,  B81B2207/07 ,  H01L2224/0235

Abstract: Expansion compensating structures are formed in redistribution layers of a wafer-level chip-scale integrated circuit package (WLCSP) or other IC package having a low-expansion substrate. The structures include micromechanical actuators designed and oriented to move solder bumps attached to them in the same direction and distance as a function of temperature as do pads to which they may be connected on a higher-expansion substrate such as a printed circuit board. Expansion compensated IC packages incorporating these expansion compensating structures are provided, as well as expansion compensated assemblies containing one or more of these IC packages. Methods of fabricating expansion compensated IC packages requiring minimal changes to existing commercial WLCSP fabrication processes are also provided. These devices and methods will result in assemblies having improved board-level reliability during thermal cycling, and allow the use of larger IC die sizes in WLCSP technology.

公开(公告)号：US20210371271A1

公开(公告)日：2021-12-02

申请号：US17331762

申请日：2021-05-27

Applicant: TallannQuest LLC DBA Apogee Semiconductor

Inventor： David A. Grant ,  Abhijeet Ghoshal

IPC: B81B3/00 ,  H02N10/00 ,  B81C1/00

Abstract: Expansion compensating structures are formed in redistribution layers of a wafer-level chip-scale integrated circuit package (WLCSP) or other IC package having a low-expansion substrate. The structures include micromechanical actuators designed and oriented to move solder bumps attached to them in the same direction and distance as a function of temperature as do pads to which they may be connected on a higher-expansion substrate such as a printed circuit board. Expansion compensated IC packages incorporating these expansion compensating structures are provided, as well as expansion compensated assemblies containing one or more of these IC packages. Methods of fabricating expansion compensated IC packages requiring minimal changes to existing commercial WLCSP fabrication processes are also provided. These devices and methods will result in assemblies having improved board-level reliability during thermal cycling, and allow the use of larger IC die sizes in WLCSP technology.