Fujitsu Corporation

Satoshi Emoto

Hidehiko Kira

Kenji Kobae

Norio Kainuma

Naoki Ishikawa

Masayuki Kitajima

Toru Okada

Hiroshi Kobayashi

Shunji Baba

Toshihiro Kusagaya

Akira Fujii

Kazuhisa Tsunoi

Takeshi Ishitsuka

Takumi Masuyama

A method of determining a reinforcement position of a circuit board includes: setting a numerical model of a circuit board in which an electronic component is mounted in a front surface by bumps, and a reinforcing member is attached to a position corresponding to a bump located in a corner part of the electrical component in a back surface; incorporating information about a stud that is located in a periphery of the electronic component and fixes the circuit board to a chassis of the electronic device; performing a simulation for obtaining values of stresses generated in bumps of corner parts when a force is applied to the electronic component from a back side of the circuit board; and determining an arrangement of the reinforcing member in accordance with a position of the stud based on the values of stresses obtained by the simulation.

Method of determining reinforcement position of circuit substrate and substrate assembly

Disclosed is a board reinforcing structure for reinforcing a circuit board in which an electronic component is mounted on a first surface, the electronic component having an electrode arranged in a rectangular-shaped region on the first surface. The board reinforcing structure includes a reinforcing member bonded to positions corresponding to corner parts of four corners of the rectangular-shaped region on a second surface provided on a side opposite to the first surface of the circuit board. In the board reinforcing structure, corresponding one of notches is formed in the reinforcing member at a position corresponding to one of the corner parts of the four corners of the rectangular-shaped region, and at least two apexes of the reinforcing member directed to an outside are formed to shape a contour thereof with the one of the notches.

Board reinforcing structure, board assembly, and electronic device

A repair apparatus includes a heating head device configured to heat a soldering member, which is soldered to a circuit board. The heating head device includes a heating head and a contact member heated by the heating head. The contact member is formed of a material having a spring characteristic and a thermal conductivity higher than a thermal conductivity of the heating head. The contact member is configured to be brought into contact with a soldered surface of the soldering member with an elastic force so as to melt a solder joining the soldering member to the circuit board.

Repair apparatus and repair method

A printed wiring board includes a first conductive paste forming a wiring pattern, and a second conductive paste including kneaded first conductive material and second conductive material whose particles are finer than those of the first conductive material.

Circuit board with kneaded conductive paste

A method of mounting a semiconductor device having bumps on a board having pads so that each of the bumps is joined to a corresponding one of the pads is provided. Adhesive to be hardened by heat is provided between the semiconductor device and the board. The method includes the steps of pressing the bumps of the semiconductor device on the pads of the board, and heating a portion in which each of the bumps and a corresponding one of the pads are in contact with each other. A pressure of the bumps to the pads reaches a predetermined value before a temperature of the adhesive to which heat is supplied in the above step reaches a temperature at which the adhesive is hardened.

Mounting method of semiconductor device

In a method of production of a multichip package module, rough-pitch bare chips are positioned at first locations on a printed-circuit board, and the rough-pitch bare chips are temporarily attached to the board at the first locations. The rough-pitch bare chips are mounted on the board at the same time by applying heat and pressure to the rough-pitch bare chips simultaneously. A respective one of fine-pitch bare chips is positioned at a respective one of second locations on the board other than the first locations, and the respective one of the fine-pitch bare chips is mounted on the board by applying heat and pressure to the fine-pitch bare chips individually, in order to produce the multichip package module.

Growing community of inventors

Kawasaki, Japan

Satoshi Emoto