Patent · US Active

No-clean low-residue solder paste for semiconductor device applications

US7767032B2 · kind B2 · utility

5Cited by

15References

18Claims

0Family size

Assignee

W. C. Heraeus GmbH · DE

Inventors

Quan Sheng · Tianjin, CN
Muriel Thomas · Dietzenbach, DE
Jens Nachreiner · Schlüchtern, DE

Key dates

Filing date	Jun 30, 2006
Grant date	Aug 3, 2010
Priority date	—
Expiry date	Oct 20, 2026

Classification

Technology area (CPC B)Performing Operations; Transporting
CPC primaryB23K35/362
WIPO fieldMachine tools
WIPO sectorMechanical engineering

Abstract

A no-clean low residue solder paste is described for die-attach dispensing or fine pitch printing of semiconductor devices. The solder paste has a homogeneous consistency with no tendency to paste separation. The ultimately remaining residue is clear and crystal like and is compatible with further processing steps without prior cleaning with a solvent to remove flux residue. The solder paste comprises a relatively low amount of rosin in combination with a viscous solvent system, thixotropic agents, activators, additives and optionally plasticizers.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.