Chemical palladium plating solution

An electroless plating, palladium salt technology, applied in liquid electroless plating, metal material coating process, coating and other directions, can solve the problem of difficult to control thickness and other problems, and achieve the effect of shortened life, long bath life and stable plating rate

Inactive Publication Date: 2010-05-19
CHANGSHA UNIVERSITY OF SCIENCE AND TECHNOLOGY
View PDF2 Cites 32 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

When the plating solution is used continuously, the plating rate of pa

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
  • Chemical palladium plating solution
  • Chemical palladium plating solution

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0040] Bath composition

[0041] PdCl 2 Mass concentration / g·L -1 2

[0042] Ethylenediamine volume concentration / mL·L -1 50

[0043] Citric acid / g·L -1 20

[0044] NaH 2 PO 2 ·H 2 O mass concentration / g·L -1 12

[0045] Thiourea / mg / L 25

[0046] The pH of the plating solution was adjusted to 9.78 with hydrochloric acid, and a 20×30mm nickel-plated printed circuit board was immersed in the plating solution for 30 minutes, and the temperature of the plating solution was 50°C. As a result, a smooth palladium film having an average thickness of 0.65 µm was produced. The palladium film was observed under a 640-fold optical microscope, and no cracks were observed. At the same time, when the plating solution was cooled, the measured pH was 9.58, with little change in pH. The MTO of palladium is greater than 3.

Embodiment 2

[0048] Bath composition

[0049] PdCl 2 Mass concentration / g·L -1 0.2

[0050] Ethylenediamine volume concentration / mL·L -1 5

[0051] Mass concentration of isopropanolamine / g·L -1 2

[0052] NaH 2 PO 2 ·H 2 O mass concentration / g·L -1 2

[0053] Thiourea / mg / L 15

[0054] The pH of the plating solution was adjusted to 9.8 with hydrochloric acid, and the 20×30mm pre-nickeled printed circuit board was immersed in the plating solution for 30 minutes, and the temperature of the plating solution was 50°C. As a result, a smooth palladium film having an average thickness of 0.15 µm was produced. The palladium film was observed under a 640-fold optical microscope, and no cracks were observed. At the same time, when the plating solution was cooled, the measured pH was 9.66, with little change in pH. The MTO of palladium is greater than 4.

Embodiment 3

[0056] Bath composition

[0057] PdCl 2 Mass concentration / g·L -1 0.6

[0058] Ethylenediamine volume concentration / mL·L -1 15

[0059] Triethanolamine / g·L -1 20

[0060] NaH 2 PO 2 ·H 2 O mass concentration / g·L -1 4

[0061] Bismuth nitrate / mg / L 20

[0062] The pH of the plating solution was adjusted to 9.88 with hydrochloric acid, and a 20×30mm nickel-plated printed circuit board was immersed in the plating solution for 30 minutes, and the temperature of the plating solution was 50°C. As a result, a smooth palladium film with an average thickness of 0.45 µm was produced. The palladium film was observed under a 640-fold optical microscope, and no cracks were observed. At the same time, when the plating solution was cooled, the measured pH was 9.53, with little change in pH. The MTO of palladium is greater than 6.

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
Film thicknessaaaaaaaaaa
Login to view more

Abstract

The invention relates to a chemical palladium plating solution, in particular to a chemical palladium plating solution which can directly form a palladium film with good adhesive force on a chemical nickel plating film formed on a printed circuit board (PCB) and does not affect the chemical nickel plating film serving as a base film. The chemical palladium plating solution contains a soluble palladium salt, a first complexing agent, a second complexing agent and a stabilizing agent, wherein the first complexing agent is one out of ammonia and diamine compounds, and the second complexing agent is one or more out of alcohol amine compounds with 2-7 carbon atoms, amine compounds with less than 7 carbon atoms and aminocarboxylic acid compounds. The palladium plating solution has stable pH, stable deposition rate, long bath service life and excellent bath stability, does not generate cracks, and can obtain the palladium plating film with very low phosphorus content and excellent corrosion resistance, solder connectivity and lead weldability.

Description

technical field [0001] The invention relates to an electroless palladium solution. Background technique [0002] The surface of the packaging carrier and other printed circuit boards has been treated with electroless nickel plating, electroless palladium plating, and immersion gold (ENEPIG), and has obtained the technical performance of nickel / palladium / gold coating, which has excellent solderability, linearity, Flatness, oxidation resistance, heat resistance and long-term reliability, etc. Palladium and gold have different deposition hardness and melting point, but both have excellent anti-oxidation performance and stable performance in high temperature and high humidity atmosphere. [0003] Electroless palladium and palladium alloys have been developed as a more economical alternative to electroless gold for some applications. Electroless palladium plating is mainly used in dual in-line package circuits (DIPS) and various other hybrid circuits, and is especially often us...

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
IPC IPC(8): C23C18/44
Inventor 吴道新肖忠良刘迎许国军
Owner CHANGSHA UNIVERSITY OF SCIENCE AND TECHNOLOGY
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