公开(公告)号：JP2000294686A

公开(公告)日：2000-10-20

申请号：JP2000065422

申请日：2000-03-09

Applicant: IBM

Inventor： JOHNSON ERIC A ,  KRESGE JOHN S

IPC: H01L23/28 ,  H01L23/12 ,  H01L23/32 ,  H01L23/498 ,  H05K1/02 ,  H05K1/11 ,  H05K1/18 ,  H05K3/00 ,  H05K3/34

Abstract: PROBLEM TO BE SOLVED: To reduce strain induced by the heat of the solder ball of a ball grid array module attached to a circuit card by a vacant part substantially surrounding the second section of a dielectric layer, and a pad containing the step positioned above the second section. SOLUTION: A solder ball 48 is attached to a circuit card bad 54, and a BGA module 40 is connected to a circuit card 50. A circular vacant space 43 of height ΔH1 inside a board 42 surrounds board material under the GBA pad 44, and a circular vacant space 56 of height ΔH2 inside a board 52 surrounds board material under a circuit card pad 54. The transformation of heat-induced strain is dispersed to the height H+ΔH1+ΔH2, whereby the strain of the solder ball decreases. This protects the preservability of solder connection, and extends the fatigue life of the BGA module, and further it can be used together with other method with a slight additional cost.

公开(公告)号：JP2004146819A

公开(公告)日：2004-05-20

申请号：JP2003343853

申请日：2003-10-01

Applicant: Internatl Business Mach Corp ,  インターナショナル・ビジネス・マシーンズ・コーポレーションInternational Business Maschines Corporation

Inventor： CALMIDI VARAPRASAD V ,  JOHNSON ERIC A ,  STUTZMAN RANDALL J

IPC: H01L23/34 ,  H01L21/56 ,  H01L23/16 ,  H01L23/36 ,  H01L23/42 ,  H01L23/473

CPC classification number: H01L23/42 ,  H01L21/563 ,  H01L23/16 ,  H01L23/473 ,  H01L2224/32225 ,  H01L2224/32245

Abstract: PROBLEM TO BE SOLVED: To provide a cooling method for an electronic assembly such as a semiconductor chip by using a thin layer of a liquid metal with a high conductivity.
SOLUTION: The liquid metal 18 is preferably gallium, or its alloy, that conducts heat from a chip 14 to a heat sink or a heat dissipation section 16. This system has more than one aperture part 38 that allows the filling of a liquid and evacuation of a space occupied by the liquid. The system also uses a flexible seal like a film held to a proper place by an O ring or a retaining ring, or a plug that seals the filling aperture part. The seal is flexible so that it deals with the expansion and contraction of the liquid as well as a phase change from a liquid phase to a solid phase.
COPYRIGHT: (C)2004,JPO

公开(公告)号：MY117209A

公开(公告)日：2004-05-31

申请号：MYPI20000780

申请日：2000-02-29

Applicant: IBM

Inventor： JOHNSON ERIC A ,  KRESGE JOHN S

IPC: H01L23/28 ,  H05K1/11 ,  H01L23/12 ,  H01L23/32 ,  H01L23/498 ,  H05K1/02 ,  H05K1/18 ,  H05K3/00 ,  H05K3/34 ,  H05K7/00

Abstract: A METHOD AND STRUCTURE FOR REDUCING THERMALLY INDUCED STRAINS ON THE SOLDER JOINTS THAT COUPLE A BALL GRID ARRAY (BGA) MODULE TO A CIRCUIT CARD, SO AS 10 IMPROVE THE FATIGUE LIFE OF THE BGA MODULE. THE THERMALY INDUCED STRAINS ARISE FROM A MISMATCH IN THERMAL EXPANSION COEFFICIENT BETWEEN THE DIELECTRIC SUBSTRATE OF THE BGA MODULE AND THE DIELECTRIC BOARD OF THE CIRCUIT CARD. THE METHOD GENERATES VOID ANNULAR REGIONS AROUND PORTION OF THE BGA DIELECTRIC SUBSTRATE TO WHICH THE BGA SOLDER BALLS ARE TO BE ATTACHED AND/OR AROUND OF THE CIRCUIT CARD DIELECTRIC MATERIAL TO WHICH THE BGA MODULE IS TO BE ATTACHED. THIS RESULTS IN THE FORMATION OF DIELECTRIC ISLANDS OR PENINSULAS THAT BOUND THE SOLDER BALLS OF THE BGA MODULE AFTER INSTALLATION ON THE CIRCUIT CARD. THE DIELECTRIC ISLANDS OR PENINSULAS THUS FORMED SERVE TO INCREASE THE EFFECTIVE HEIGHT OVER WHICH THE DIFFERENTIAL EXPANSION IS ACCOMMODATED, THEREBY REDUCING THE STRAINS THOUGHOUT THE SOLDER JOINTS. ADDITIONALLY, THE VOID ANNULAR REGIONS PROVIDE SPACE FOR THE DEFORMATION OF THE DIELECTRIC ISLANDS OR PENINSULAS, THEREBY INCREASING THEIR COMPLIANCE AND TRANSFERRING STRAINS FROM THE SOLDER JOINTS TO THE DIELECTRIC ISLAND OR PENINSULAS.

公开(公告)号：CA2291402A1

公开(公告)日：2000-09-19

申请号：CA2291402

申请日：1999-12-02

Applicant: IBM

Inventor： JOHNSON ERIC A ,  KRESGE JOHN S

IPC: H01L23/28 ,  H01L23/12 ,  H01L23/32 ,  H01L23/498 ,  H05K1/02 ,  H05K1/11 ,  H05K1/18 ,  H05K3/00 ,  H05K3/34 ,  H05K3/22

Abstract: A method and structure for reducing thermally induced strains on the solder joints that couple a ball grid array (BGA) module to a circuit card, so as to improve the fatigue life of the BGA module. The thermally induced strains arise from a mismatch in thermal expansion coefficient between the dielectric substrate of the BGA module and the dielectric board of the circuit card. The method generates void annular regions around portions of the BGA dielectric substrate to which the BGA solder balls are to be attached and/or around portions of the circuit card dielectric material to which the BGA module is to be attached. This results in the formation of dielectric islands or peninsulas that bound the solder balls of the BGA module after installation on the circuit card. The dielectric islands or peninsulas thus formed serve to increase the effective height over which the differential expansion is accommodated, thereby reducing the strains throughout the solder joints. Additionally, the void annular regions provide space for the deformation of the dielectric islands or peninsulas, thereby increasing their compliance and transferring strain from the solder joints to the dielectric islands or peninsulas.

公开(公告)号：DE3675831D1

公开(公告)日：1991-01-10

申请号：DE3675831

申请日：1986-05-28

Applicant: IBM

Inventor： JOHNSON ERIC A ,  PRICE II

IPC: B23Q17/09 ,  B23B47/24 ,  B23B49/00 ,  G01H17/00

Abstract: A failure detector (12) detects breakage in a machine tool cutting element (22), such as a drill bit, by use of an accelerameter (62, 58) supported against a workpiece (16) being operated on by the cutting element. Vibrations are induced in the workpiece by the cutting operation, the vibrations having spectral components in the audio frequency range which are characteristic of proper operation of the cutting element (22), the spectral components changing upon a breakage of the cutting element. A voltage (40) produced by a positioning mechanism (38, 36) of the cutting element identifies the location of the cutting element relative to the workpiece. A bandpass filter (46) separates the spectral components associated with proper operation from spectral components associated with faulty operation. Logic circuitry (52) monitors the joint occurrence (122, 100) of the spectral components of proper operation with the position of the cutting element at the site of the workpiece so as to permit the signaling (56) of a cutting tool failure during operation on the workpiece.

公开(公告)号：BR0004882A

公开(公告)日：2001-10-02

申请号：BR0004882

申请日：2000-10-17

Applicant: IBM

Inventor： CALETKA DAVID V ,  JOHNSON ERIC A

IPC: H01L21/60 ,  H01L23/498 ,  H05K1/11 ,  H05K3/34 ,  H01L21/44 ,  H01L23/48

Abstract: A method of forming BGA interconnections having improved fatigue life is disclosed. In particular, a combination of mask-defined and pad-defined solder joints are selectively positioned within the BGA package. The mask-defined solder joints possess a high equilibrium height, which forces the pad-defined solder joints to elongate, thereby making the pad-defined solder joints more compliant. Further, the pad-defined solder joints posses a slightly longer fatigue life because the stress concentrations found in the mask-defined solder joints are not present in the pad-defined solder joints. Therefore, the fatigue life of BGA packages is increased by implementing a majority of mask-defined solder joints to maintain a high equilibrium height, and selectively placing pad-defined solder joints in high stress areas of the BGA package.

公开(公告)号：GB2349014A

公开(公告)日：2000-10-18

申请号：GB0004103

申请日：2000-02-23

Applicant: IBM

Inventor： JOHNSON ERIC A ,  KRESGE JOHN S

IPC: H01L23/28 ,  H01L23/12 ,  H01L23/32 ,  H01L23/498 ,  H05K1/02 ,  H05K1/11 ,  H05K1/18 ,  H05K3/00 ,  H05K3/34 ,  H01L23/485

Abstract: A method for forming an electronic structure comprises removing a portion of a dielectric layer from a substrate 52 to form a void 56. The void portion 56 may completely or partly surround a second portion 57 of the dielectric layer. A conductive pad 54 is formed on the second portion 57 of dielectric. The void may be formed using a laser. The method and structure may be used to reduce thermally induced strains on solder joints 48 that couple a ball grid array (BGA) module 40 to a circuit card 50.

公开(公告)号：CA2291402C

公开(公告)日：2004-11-16

申请号：CA2291402

申请日：1999-12-02

Applicant: IBM

Inventor： JOHNSON ERIC A ,  KRESGE JOHN S

IPC: H01L23/28 ,  H01L23/12 ,  H01L23/32 ,  H01L23/498 ,  H05K1/02 ,  H05K1/11 ,  H05K1/18 ,  H05K3/00 ,  H05K3/34 ,  H05K3/22

Abstract: A method and structure for reducing thermally induced strains on the solder joints that couple a ball grid array (BGA) module to a circuit card, so as to improve the fatig ue life of the BGA module. The thermally induced strains arise from a mismatch in thermal expansion coefficient between the dielectric substrate of the BGA module and the dielectric board of the circuit card. The method generates void annular regions around portions of the BGA dielectric substrate to which the BGA solder balls are to be attached and/or around portions of the circuit ca rd dielectric material to which the BGA module is to be attached. This results in the formation of dielectric islands or peninsulas that bound the solder balls of the BGA module after installation on the circuit card. The dielectric islands or peninsulas thus formed serve to increase the effective height over which the differential expansion is accommodated, thereby reducing the strains throughout the solder joints. Additionally, the void annular regions provide space for the deformation of the dielectric islands or peninsulas, thereby increasing their compliance and transferring strain from the solder joints to the dielectric islands or peninsulas.

公开(公告)号：HK1031041A1

公开(公告)日：2001-05-25

申请号：HK01101927

申请日：2001-03-16

Applicant: IBM

Inventor： JOHNSON ERIC A ,  KRESGE JOHN S

IPC: H01L23/28 ,  H01L23/12 ,  H01L23/32 ,  H01L23/498 ,  H05K1/02 ,  H05K1/11 ,  H05K1/18 ,  H05K3/00 ,  H05K3/34 ,  H01L

Abstract: A method and structure for reducing thermally induced strains on the solder joints that couple a ball grid array (BGA) module to a circuit card, so as to improve the fatigue life of the BGA module. The thermally induced strains arise from a mismatch in thermal expansion coefficient between the dielectric substrate of the BGA module and the dielectric board of the circuit card. The method generates void annular regions around portions of the BGA dielectric substrate to which the BGA solder balls are to be attached and/or around portions of the circuit card dielectric material to which the BGA module is to be attached. This results in the formation of dielectric islands or peninsulas that bound the solder balls of the BGA module after installation on the circuit card. The dielectric islands or peninsulas thus formed serve to increase the effective height over which the differential expansion is accommodated, thereby reducing the strains throughout the solder joints. Additionally, the void annular regions provide space for the deformation of the dielectric islands or peninsulas, thereby increasing their compliance and transferring strain from the solder joints to the dielectric islands or peninsulas.

公开(公告)号：HK1029660A1

公开(公告)日：2001-04-06

申请号：HK01100424

申请日：2001-01-16

Applicant: IBM

Inventor： DIBBLE ERIC P ,  JOHNSON ERIC A ,  PHILLIPS RAYMOND A JR

IPC: H01L21/58 ,  H01L21/60 ,  H01L23/36 ,  H01L23/373 ,  H01L

Abstract: An improved bonding system is provided in which a metal heat spreader is bonded to semiconductor chip. A two adhesive system is used in which a first adhesive demonstrates high bond strength with a second adhesive exhibits high thermal conductivity.