Mitsubishi Denki Kabushiki Kaisha

Shin-Etsu Chemical Co., Ltd.

Toppan Printing Co., Ltd.

Toppan Inc.

Shin-Etsu Chemical Ltd., Co.

Noriaki Higuchi

Toshio Shiobara

Kazutoshi Tomiyoshi

Takaaki Fukumoto

Eiichi Asano

Koji Futatsumori

Haruo Shimamoto

Tomoyuki Marugame

Masami Inokuchi

Hideya Yagoura

Hui Teng Teoh

Chiat Hooi Keow

Shingo Nonaka

A display technique capable of displaying special images. A display includes a light shielding layer having a plurality of slits arranged at intervals in a width direction thereof, and an image recording layer that faces a first major surface of the light shielding layer at an interval and in which a latent image is recorded, the latent image being rendered visible by being partially concealed by the light shielding layer.

Display

An image producing device that produces an image by thermally transferring an image pattern from a transfer ribbon to a transfer medium. The device includes take-up means for taking up the transfer ribbon, supply means for supplying the transfer ribbon according to the taking up of the transfer ribbon performed by the take-up means, thermal transfer means for thermally transferring an image to the transfer medium by bringing the transfer ribbon that is between the supply means and the take-up means into contact with the transfer medium, and a regulating means for regulating the supply of the transfer ribbon performed by the supply means.

Image producing device, transfer ribbon and image producing method

By removing a fraction of fine particles having a particle size of less than 2 &mgr;m from starting inorganic filler particles having a mean particle size of 10-50 mm and adding thereto particles having a mean particle size of 0.1-2 &mgr;m and a specific surface area of 3-10 m,/g (BET), there is obtained a particulate inorganic filler having a mean particle size of 5-40 &mgr;m. When a large amount of the inorganic filler is loaded in an epoxy resin composition, the composition maintains a low melt viscosity enough to mold and is effective for encapsulating a semiconductor device without causing die pad deformation and wire deformation. The encapsulated semiconductor device is highly reliable.

Inorganic filler, epoxy resin composition, and semiconductor device

In an epoxy resin composition comprising an epoxy resin, a curing agent, and at least 70% by weight of an inorganic filler, at least one of the epoxy resin and the curing agent has such a molecular weight distribution as to provide an average dispersity Mw/Mn of less than 1.6, a two-nucleus compound content of less than 8% by weight and a seven- and more-nucleus compound content of less than 32% by weight. When the composition is cured at 180.degree. C. for 90 seconds into a primary product having Tg1 and the primary product postcured at 180.degree. C. for 5 hours into a secondary product having Tg2, the relationship: (Tg2-Tg1)/Tg2&lt;0.1 is satisfied. The composition is fast-curing and effectively moldable and cures into a reliable product without a need for postcure.

Epoxy resin compositions and semiconductor devices encapsulated therewith

In an epoxy resin composition comprising an epoxy resin, a curing agent, and 80-90 wt % of a particulate inorganic filler, fine particles having a particle size of less than 3 .mu.m account for 10-40 wt % of the inorganic filler, and the inorganic filler has a specific surface area of less than 2.5 m.sup.2 /g as measured by a nitrogen adsorption BET method. The inorganic filler satisfies that when a blend of a bisphenol F type liquid epoxy resin having a viscosity of 30-45 poises at 25.degree. C. as measured by Gardner-Holdt method with 75 wt % of the inorganic filler is measured for viscosity at 25.degree. C. by means of an E type viscometer, the viscosity at a shear rate of 0.6 s.sub.-1 is less than 50,000 poises and the ratio of the viscosity at a shear rate of 0.6 s.sup.-1 to the viscosity at a share rate of 10 s.sup.-1 is less than 2.5/1. The epoxy resin composition has a low melt viscosity enough to mold on semiconductor devices without die pad and wire deformation.

Epoxy resin composition and semiconductor device encapsulated therewith

By removing a fraction of fine particles having a particle size of less than 2 .mu.m from starting inorganic filler particles having a mean particle size of 10-50 .mu.m and adding thereto particles having a mean particle size of 0.1-2 .mu.m and a specific surface area of 3-10 m.sup.2 /g (BET), there is obtained a particulate inorganic filler having a mean particle size of 5-40 .mu.m. When a large amount of the inorganic filler is loaded in an epoxy resin composition, the composition maintains a low melt viscosity enough to mold and is effective for encapsulating a semiconductor device without causing die pad deformation and wire deformation. The encapsulated semiconductor device is highly reliable.

A resin encapsulating molding die for manufacturing a semiconductor device includes a cavity piece having a cavity on which a lead frame with a mounted semiconductor element may be placed, with the semiconductor element in the cavity, and a gate piece having a gate portion including a sub-runner through which a molten resin for encapsulating the semiconductor element is introduced into the cavity, the gate piece being detachable from the cavity piece. The molding die also includes a sealing dam disposed adjacent the sub-runner for blocking flow of molten resin from the sub-runner toward leads of the lead frame. The sealing dam may be a clamp structure for clamping the leads closest to the gate portion, the sealing dam and cavity piece may be a continuous unitary structure, and the sealing dam may have a parting surface substantially coplanar with a parting surface of the cavity piece.

Resin encapsulating molding die for manufacturing a semiconductor device

A semiconductor device includes a molded resin encapsulating a semiconductor chip, outer leads extending from the molded resin and having free ends, and a resin layer connecting and supporting the outer leads along the entire length of the outer leads. The resin layer may have an activating ability for soldering. A method for manufacturing a semiconductor device includes preparing a semiconductor device having a molded resin and a plurality of outer lead portions extending from the molded resin and connected to a lead frame, forming a resin film on and between the outer lead portions; cutting the lead portions to provide cantilevered outer leads having free ends; lead-forming the outer leads with lead-forming dies while heating the resin film to form a resin layer connecting and supporting the outer leads along the entire lengths of the outer leads, and taking the semiconductor device out of the lead-forming dies after the resin layer has been cured.

Growing community of inventors

Tokyo, Japan

Noriaki Higuchi