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US 7,842,552 B2Granted
Semiconductor chip packages having reduced stress
AssigneeInternational Business Machines Corporation
InventorsJohn Peter Karidis, Mark Delorman Schultz
Life of this patent
Estimating the term…
Abstract
A structure and a method for forming the same. The structure includes (i) a carrier substrate which includes substrate pads, (ii) a chip physically attached to the carrier substrate, and (iii) a first frame physically attached to the carrier substrate. A CTE (coefficient of thermal expansion) of the first frame is substantially lower than a CTE of the carrier substrate.
Claims17
A method, comprising:
- providing a carrier substrate and a chip, wherein the carrier substrate includes first substrate pads and second substrate pads, and wherein the chip includes first solder balls;
- placing the chip on the carrier substrate such that the first solder balls are in direct physical contact with the first substrate pads of the carrier substrate such that at least one solder ball of the first solder balls is in direct physical contact with at least one substrate pad of the first substrate pads;
- raising both the carrier substrate and the chip from an initial temperature up to a bonding temperature that is higher than the initial temperature resulting in the first solder balls being physically attached to the first substrate pads of the carrier substrate such that at least one solder ball of the first solder balls is physically attached to at least one substrate pad of the first substrate pads;
- cooling both the carrier substrate and the chip from the bonding temperature down to a final temperature after said raising is performed;
- attaching a first frame to the carrier substrate before a temperature of the carrier substrate and the chip reaches the final temperature as a result of said cooling being performed, wherein a CTE (coefficient of thermal expansion) of the first frame is substantially lower than a CTE of the carrier substrate, wherein said attaching the first frame is performed before said placing is performed;
- and
- before said attaching the first frame is performed, pre-stretching the carrier substrate resulting in the carrier substrate being under tensile stress,
- wherein either said attaching the first frame is performed while said cooling is performed or said attaching the first frame is performed when a temperature of both the carrier substrate and the chip reaches the bonding temperature as a result of said raising being performed.
5 more elements
A method, comprising:
- providing a carrier substrate and a chip, wherein the carrier substrate includes first substrate pads and second substrate pads, and wherein the chip includes first solder balls;
- placing the chip on the carrier substrate such that the first solder balls are in direct physical contact with the first substrate pads of the carrier substrate such that at least one solder ball of the first solder balls is in direct physical contact with at least one substrate pad of the first substrate pads;
- raising both the carrier substrate and the chip from an initial temperature up to a bonding temperature that is higher than the initial temperature resulting in the first solder balls being physically attached to the first substrate pads of the carrier substrate such that at least one solder ball of the first solder balls is physically attached to at least one substrate pad of the first substrate pads;
- cooling both the carrier substrate and the chip from the bonding temperature down to a final temperature after said raising is performed;
- attaching a first frame to the carrier substrate before a temperature of the carrier substrate and the chip reaches the final temperature as a result of said cooling being performed, wherein a CTE (coefficient of thermal expansion) of the first frame is substantially lower than a CTE of the carrier substrate;
- and
- attaching a second frame to the carrier substrate, wherein the carrier substrate is sandwiched between the first and second frames, and wherein said attaching the first frame and said attaching the second frame are performed simultaneously.
4 more elements
A method, comprising:
- providing a carrier substrate and a chip, wherein the carrier substrate includes first substrate pads and second substrate pads, and wherein the chip includes first solder balls;
- placing the chip on the carrier substrate such that the first solder balls are in direct physical contact with the first substrate pads of the carrier substrate such that at least one solder ball of the first solder balls is in direct physical contact with at least one substrate pad of the first substrate pads;
- raising both the carrier substrate and the chip from an initial temperature up to a bonding temperature that is higher than the initial temperature resulting in the first solder balls being physically attached to the first substrate pads of the carrier substrate such that at least one solder ball of the first solder balls is physically attached to at least one substrate pad of the first substrate pads;
- cooling both the carrier substrate and the chip from the bonding temperature down to a final temperature after said raising is performed;
- attaching a first frame to the carrier substrate before a temperature of the carrier substrate and the chip reaches the final temperature as a result of said cooling being performed, wherein a CTE (coefficient of the final expansion) of the first frame is substantially lower than a CTE of the carrier substrate, wherein said attaching the first frame is performed before said placing is performed;
- and
- before said attaching the first frame is performed, pre-stretching the carrier substrate resulting in the carrier substrate being under tensile stress, wherein all sides of the carrier substrate have edges, wherein said pre-stretching is performed at room temperature and comprises gripping all sides of the carrier substrate at the edge of the sides of the carrier substrate and then pulling the gripped carrier substrate to stretch the carrier substrate to place the carrier substrate under tensile stress.
4 more elements
Dependencies are inferred from the claim text.