Tin plating bath and a method for depositing tin or tin alloy onto a surface of a substrate

A technology for electroplating baths and tin alloys, applied in circuits, electrical components, electrical solid devices, etc., can solve problems such as difficult control of electroplating results, and achieve the effect of high electroplating rate

Pending Publication Date: 2022-01-04
ATOTECH DEUT GMBH
View PDF11 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Such behavior is highly undesirable as it makes it extremely difficult to control plating results such as tin deposit uniformity and thickness

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
  • Tin plating bath and a method for depositing tin or tin alloy onto a surface of a substrate

Examples

Experimental program
Comparison scheme
Effect test

example

[0106] Unless specified differently below, the products were used as described (concentrations, parameters, other derivatives) in the corresponding technical data sheets (as available on the filing date). Practical applications usually require a plating rate of at least 2 μm / h.

[0107] Determining the thickness of metal or metal alloy deposits : The deposit thickness was measured at 10 positions on each substrate and used to determine the layer thickness by XRF using the XRF instrument Fischerscope XDV-SDD (Helmut Fischer GmbH, Germany). Layer thicknesses can be calculated from such XRF data by assuming a layered structure of the deposit. Alternatively, the thickness of the deposit was measured with a quartz crystal microbalance (SRS QCM200, Stanford Research Systems, Inc.) according to the frequency variation in the quartz crystal.

[0108] Measurement of Plating Rate : The plating rate is obtained by dividing the thickness of the tin deposit by the time required to obt...

example 1

[0110] Invention example 1: Sodium sulfite as accelerator in electroless tin plating bath

[0111] In a beaker, 660.66 g of potassium pyrophosphate was dissolved in deionized water and 220 g of titanium(III) chloride was added to the solution and dissolved while stirring the solution. The volume of the resulting solution was adjusted to 1000 mL with deionized water.

[0112] The resulting solution was stirred at 60 °C for two to three hours until a dark blue solution with precipitate formed. The solution was filtered (10 μm) and the titanium concentration was determined via titration. The titanium concentration should generally be in the range of 190 to 215 mM. The resulting solution has a pH of about 7.8 to 8.3.

[0113] The solution described above is used to prepare the tin electroplating bath of the present invention, which comprises the following components:

[0114] c(Sn 2+ )=60mmol / L

[0115] c(Ti 3+ )=60mmol / L

[0116] c (pyrophosphate) = 700mmol / L

[0117] ...

example 2

[0124] Inventive Example 2: Sulfur as Accelerator in Electroless Tin Plating Baths

[0125] The method described for Inventive Example 1 was repeated, but sodium sulfite was replaced with 1 ppm sulfur nanoparticles and the aerodynamic diameter measured by an aerodynamic particle size analyzer (APS) was below 100. The results are summarized in Table I.

[0126] The tin electroplating bath was stable and exhibited no precipitation or precipitation.

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

No PUM Login to view more

Abstract

The present invention concerns a tin plating bath comprising tin ions; titanium ions as reducing agent suitable to reduce tin ions to metallic tin; and at least one compound selected from the group consisting sulfites, dithionites, thiosulfates, tetrathionates, polythionates, disulfites, sulfides, disulfide, polysulfide, elemental sulfur or mixtures thereof. The present invention further discloses a method of depositing tin or a tin alloy onto a surface of a substrate. The tin plating bath is particularly suitable to be used in the electronics and semiconductor industry.

Description

technical field [0001] The present invention relates to a tin electroplating bath comprising tin ions and titanium ions as a reducing agent suitable for reducing the tin ions to metallic tin. The invention further relates to a method of depositing tin or tin alloys on the surface of a substrate. Tin electroplating baths are particularly suitable for depositing tin or tin alloys on at least one surface of a substrate, preferably used in the electronics and semiconductor industries. Background technique [0002] Deposits of tin and tin alloys on electronic components such as printed circuit boards, IC substrates and semiconductor wafers are used inter alia as solderable and bondable finishes in subsequent manufacturing steps of such electronic components. [0003] Tin and tin alloy deposits are typically formed on metal contact areas, such as contact pads and bump structures. The contact areas are usually made of copper or copper alloys. Where such contact pads are electric...

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): C23C18/52C23C18/16C23C18/48
CPCC23C18/52C23C18/48C23C18/1619C23C18/16H01L24/03H01L24/11H01L24/13H01L2224/03464
Inventor K·图纳
Owner ATOTECH DEUT GMBH
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