US 6,486,411 B2Granted

Semiconductor module having solder bumps and solder portions with different materials and compositions and circuit substrate

AssigneeHitachi, Ltd.

InventorsKazuma Miura, Hanae Shimokawa, Koji Serizawa, Tasao Soga, Tetsuya Nakatsuka

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Abstract

A semiconductor module solder bonding of high reliability in which the heat resisting properties of the circuit substrate and electronic parts are taken into consideration. In order to achieve this, there are provided semiconductor devices each having solder bumps as external pads, and a circuit substrate bonded to the external pads of each of the semiconductor devices through a solder paste, each of the solder bumps being made of a first lead-free solder, the solder paste being made of a second lead-free solder having a melting point lower than that of the first lead-free solder.

Claims26

Dependent claims

A semiconductor module comprising:

a semiconductor device provided with solder bumps;
a substrate provided on a face thereof with external terminals each having a solder portion, on which substrate the semiconductor device is mounted;
and
connection portions through which said semiconductor device is bonded to said substrate, each of said connection portions including respective ones of the solder bumps and solder portions which are bonded to each other;
said solder bumps being made of a first Pb-free solder containing silver;
said solder portions of said external terminals being made of a second Pb-free solder containing silver which second solder has a composition different from that of the first Pb-free solder;
said solder portions of said external terminals having a melting point lower than that of the solder bumps of the semiconductor device;
and
a content of silver contained in said solder bumps being lower than that of silver contained in said solder portions of said external terminals of the substrate.

6 more elements

Dependencies are inferred from the claim text.

Facts

Application: 09/811,445Filed 20 Mar 2001
Priority: JP 2000-18071212 Jun 2000
Published: US 2001/0050181 A113 Dec 2001
Granted: 26 Nov 2002
Term ends: Not estimatedThe source records don’t support an estimate.

Classification17 codes

H05K 3/346
By soldering: solder materials or compositions specially adapted therefor
H05K 3/3436
Leadless components: having an array of bottom contacts, e.g. pad grid array or ball grid array components
H05K 2201/10992
Other details of electrical connections: using different connection materials, e.g. different solders, for the same connection
H10W 72/90
Interconnections or connectors in packages: bond pads, in general