Invention Grant
- Patent Title: Reduction of chip carrier flexing during thermal cycling
- Patent Title (中): 在热循环期间减少芯片载体弯曲
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Application No.: US10262023Application Date: 2002-09-30
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Publication No.: US06818972B2Publication Date: 2004-11-16
- Inventor: Lisa J. Jimarez , Miguel A. Jimarez
- Applicant: Lisa J. Jimarez , Miguel A. Jimarez
- Main IPC: H01L23495
- IPC: H01L23495

Abstract:
A method and structure for reducing chip carrier flexing during thermal cycling. A semiconductor chip is coupled to a stiff chip carrier (i.e., a chip carrier having an elastic modulus of at least about 3×105 psi), and there is no stiffener ring on a periphery of the chip carrier. Without the stiffener ring, the chip carrier is able to undergo natural flexing (in contrast with constrained flexing) in response to a temperature change that induces thermal strains due to a mismatch in coefficient of thermal expansion between the chip and the chip carrier. If the temperature at the chip carrier changes from room temperature to a temperature of about −40° C., a maximum thermally induced displacement of a surface of the chip carrier is at least about 25% less if the stiffener ring is absent than if the stiffener ring is present. Since a propensity for cracking of the stiff chip carrier increases as the thermally induced displacement increases, the present invention, which avoids use of the stiffener ring, improves a structural integrity of the chip carrier.
Public/Granted literature
- US20030034566A1 Reduction of chip carrier flexing during thermal cycling Public/Granted day:2003-02-20
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