Lead-free solder alloy comprising sn, bi and at least one of mn, sb, cu and its use for soldering an electronic component to a substrate

A technology of lead-free solder alloy and electronic components, which is applied in the direction of assembling printed circuits, electrical components, welding media, etc. with electrical components, and can solve the problems of electroless nickel plating-gold is not a finish, etc.

Inactive Publication Date: 2019-05-21
英特福莱电子有限公司
View PDF9 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0009] Also, electroless nickel-gold is not the only relevant finish

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Lead-free solder alloy comprising sn, bi and at least one of mn, sb, cu and its use for soldering an electronic component to a substrate
  • Lead-free solder alloy comprising sn, bi and at least one of mn, sb, cu and its use for soldering an electronic component to a substrate
  • Lead-free solder alloy comprising sn, bi and at least one of mn, sb, cu and its use for soldering an electronic component to a substrate

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0035] To test the reliability, an X-ray analysis is used to test for void formation in so-called QFN packages. A QFN package is a package that has an exposed die pad surrounded by a plurality of contact pads. The QFN package is a popular choice because of its thin and small profile, low weight, and good thermal properties due to the exposed die pad and reduced lead inductance. It is similar to eg QFP (Quad Flat Pack). In 2013, approximately 32.6 billion QFN packages were assembled. Additional variants of the QFN package are most likely to be developed. A QFN package typically includes one or more integrated circuits. A plurality of contact pads are present on all four sides of the package, typically extending on both the sides and the bottom surface of the package. The number of contact pads is for example in the range of 20-100. The pitch (center-to-center distance between adjacent contact pads) is for example in the range of 0.3mm-0.7mm, and the width of the contact pa...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
melting pointaaaaaaaaaa
Login to view more

Abstract

A solder alloy comprises 38.0-42.0 wt% bismuth (Bi), 0.01-2 wt% of at least one further element chosen from the group of manganese (Mn), antimony (Sb) and copper (Cu), the balance being tin (Sn), andis at least substantially free of nickel (Ni), and further preferably substantially free of silver (Ag). The solder alloy may be combined with a halide-free solder flux to constitute a solder paste, solder bath or solder wire. The solder paste is for instance used for soldering electronic component packages such as quad flat non-leaded (QFN) packages or for soldering surface mount devices (SMD), resulting in low void formation. The solder alloy may also be applied by means of wave-soldering or selective soldering.

Description

field of invention [0001] The present invention relates to lead free tin-bismuth solder compositions. [0002] The invention also relates to the use of such a lead-free tin-bismuth solder composition for soldering an electronic component package to a substrate provided with a plurality of contacts and an exposed die Die pads, the contacts and the die pads are soldered to associated contacts on the substrate. Background of the invention [0003] Traditionally, solder compositions are based on eutectic lead-tin alloys, which have a melting point of about 180°C. This composition is known to have good adhesive properties. However, due to the toxicity of lead, the use of this solder composition is no longer permitted. Over the past 20 years, tin-based solders have become the standard material for soldering in microelectronics. More specifically, the tin-based solder is an alloy of tin (Sn), silver (Ag) and copper (Cu), also called SAC solder. Typically, the tin content excee...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): B23K35/26H05K3/34C22C13/02B23K35/362
CPCB23K35/262B23K35/362B23K35/025C22C13/00C22C13/02H01L24/16H05K3/3457H05K3/3489H01L2224/131B23K35/26B23K35/36B23K35/0222B23K35/0244H01L23/49513H05K3/3485B23K35/264B23K35/0277H01L2924/014C22C12/00
Inventor 丹尼尔·韦尔克霍芬安尼克·佩特斯拉尔夫·洛维特伊莎贝尔·玛丽斯巴特·范德利斯东克史蒂文·特里斯泽维斯基
Owner 英特福莱电子有限公司
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap