Other

Kabushiki Kaisha Toshiba

Sumitomo Metal Industries, Inc.

Sumitomo Metal (smi) Electronics Devices, Inc.

Sumitomo Metal Ceramics Inc.

Hiroshi Takamichi

Takashi Takahashi

Keiichi Yano

Kazuo Kimura

Toshihiko Kubo

Yoshitoshi Sato

Shizuki Hashimoto

Yoshikazu Nakada

Kouji Yamakawa

Takuji Ito

Masafumi Fujii

Akihiro Hidaka

Toshishige Yamamoto

A ball-grid array connector structure for an electronic package in which the ball pitch can be reduced to increase the packaging density has a plastic substrate having at least one hollow through-hole and an electrode covering the wall of the through-hole and forming an electrode pad surrounding the through-hole on each surface of the substrate. A metallic ball is joined, either directly or through a solder or a combination of a metallic bump and a solder, to the electrode pad on at least one surface of the substrate at the position of the through-hole. The connector structure can be formed either by sealing an open end of the through-hole on the side to which the ball is not joined, or increasing the pressure within the through-hole by a pressure-control mechanism, before the through-hole is blocked by reflowing the ball itself or the metallic bump or solder used to connect the ball.

Method of forming connector structure for a ball-grid array

In order that popcorning and delamination resulting from moisture vapor in a semiconductor package may be prevented, a vent hole is formed in a die-bonding area of a plastic substrate so as to extend vertically through the substrate. An upper open end of the vent hole is covered with a solder resist film and a semiconductor chip is die-bonded on the solder resist film. In the die-bonding step, the solder resist film prevents an adhesive agent from flowing into the vent hole through the upper open end, so that gas permeability of the vent hole can be ensured. Furthermore, since the solder resist film has gas permeability, moisture vapor in the package is released outside through the vent hole and the solder resist film during a reflow heating.

Semiconductor package with improved moisture vapor relief function and

A semiconductor package comprises an aluminum nitride substrate having a semiconductor element mounted thereon, a lead frame junctioned to the side of the aluminum nitride substrate directly contacting the mounted semiconductor element, and a ceramic sealing member junctioned to the aluminum nitride substrate so as to seal the semiconductor element. The lead frame has a coating layer of a nonmagnetic metallic material formed in a thickness of not more than 20 .mu.m on only one of the opposite surfaces of a lead frame matrix made of a ferromagnetic metal to which a bonding wire is to be junctioned. The layer of the nonmagnetic metallic material is formed by any of such thin film forming technique as the vacuum deposition technique, the spattering technique, and the plating technique. The coating layer formed on only one of the opposite surfaces of the lead frame matrix is capable of amply curbing the resistance and the dependency of inductance on frequency. The aluminum nitride substrate is capable of imparting an ideal ability to radiate heat. The semiconductor package enables a high-speed quality semiconductor element having such a high system clock frequency as is not less than 50 MHz to be operated stably.

Semiconductor package using an aluminum nitride substrate

Growing community of inventors

Ube, Japan

Hiroshi Takamichi