Semiconductor devices

Active solid-state devices (e.g. – transistors – solid-state diode – Encapsulated

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C257S778000

Reexamination Certificate

active

06498400

ABSTRACT:

FIELD OF THE INVENTION
This invention relates to hot-melt adhesive sheets and semiconductor devices. More particularly, this invention relates to a hot-melt adhesive sheet that provides very precise bonding and exhibits a stress-relaxation capacity. It also relates to highly reliable semiconductor devices in which the semiconductor element therein is bonded to its element attachment site using this hot-melt adhesive sheet.
BACKGROUND OF THE INVENTION
Hot-melt adhesives—which have the capacity to bond various substrates once the adhesive has been softened by heating—also find use as adhesives for bonding semiconductor elements to the corresponding element attachment sites. For example, Japanese Patent Application Laid Open (Kokai or Unexamined) Number Sho 61-201432 (201,432/1986) teaches a method in which a hot-melt adhesive is first coated on an integrated circuit-bearing silicon wafer and the semiconductor elements cut from that wafer are then bonded to their attachment sites.
However, since hot-melt adhesives employ a heat softening regimen, their use to bond a semiconductor element to its attachment site has been associated with the problem of an inability to achieve highly precise bonding due to outflow of the adhesive into the area surrounding the element and variations in the thickness of the adhesive. Moreover, hot-melt adhesives have had a poor stress-relaxation capacity under challenge by thermal shock, which has resulted in a reduced device reliability for semiconductor devices containing a semiconductor element that has been bonded to its attachment site by a hot-melt adhesive.
SUMMARY OF THE INVENTION
The present invention is directed to a semiconductor device comprising a semiconductor element; a substrate; and a hot-melt adhesive sheet bonding the semiconductor element to the substrate, wherein the hot-melt adhesive sheet comprises a spacer having the form of a sheet and a hot melt adhesive on both sides of the spacer.
The present invention is also directed to a semiconductor device comprising a semiconductor element; a substrate; and a hot-melt adhesive sheet bonding the semiconductor element to the substrate, wherein the hot-melt adhesive sheet comprises a mixture of a hot melt adhesive and a spacer, wherein the adhesive is selected from a silicone-modified epoxy resin adhesive, a silicone adhesive, and a silicone-modified polyimide adhesive, and the spacer has the form of particles.


REFERENCES:
patent: 4624724 (1986-11-01), Davis
patent: 5538771 (1996-07-01), Nakayama et al.
patent: 5614316 (1997-03-01), Hashimoto et al.
patent: 5670251 (1997-09-01), Difrancesco
patent: 61-201432 (1986-09-01), None

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Semiconductor devices does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Semiconductor devices, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Semiconductor devices will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-2949664

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.