Query: non-cyanide gold plating

Candidate papers:

abstract: The plated gold being used by the electronics industry can be broadly classified into two categories: soft gold and hard gold. Soft gold is used for circuit metallization and for bonding semiconductor chips, while hard gold is indispensable as the contact material on electrical connectors, electromechanical relays, and printed circuit boards. The traditional baths from which to plate soft gold as well as hard gold contain the cyanide complex, [Au(CN)2] as the source of gold, which liberates free cyanide ions during the plating. The free cyanide is not only highly toxic but also attacks photoresists used to delineate circuit patterns and bonding pads. For these reasons, noncyanide baths are in use to plate soft gold, whereas hard gold can be plated only from cyanide baths at present. In this presentation, the current status of both electrolytic and electroless non cyanide processes for plating soft gold will be reviewed.
author_names: Masaru Kato

Yutaka Okinaka
title: Some recent developments in non cyanide gold plating for electronics applications
year: 2004

abstract: Non cyanide gold plating bath (1) containing gold ions with the following compound (Chemical 1) represented by the chemical formula.
title: The method of manufacturing a non cyanide gold plating bath and the non cyanide gold plating bath
year: 2013

abstract: (Problem) Provided are a non cyanide electrolytic gold plating bath for forming gold bumps having bump hardness and bump shape suitable for electrode bonding with a substrate electrode, and a gold bump forming method using the gold plating bath. (Solution means) Containing gold sulfite or gold ammonium sulfite, conducting salt, crystal stabilizer, crystal regulator, buffer, and polishing agent, the content of gold alkali sulfite or ammonium sulfite as gold concentration 1 to 20 g l, the conductive salt is sodium sulfite, the content is 5 to 150 g l, and the content of the brightening agent is 0.5 to 100 mmol l; Gold plating bath. The above mentioned polishing agent is preferably one or two or more compounds selected from sulfoxides and or sulfones.
author_names: syoji isijaki

yuuki nakamura

dakasi yamada
title: Non cyanide gold plating bath for bump and forming method of gold bump
year: 2012

abstract: A sulfite gold plating solution is capable of stable operation at pH values as low as 4.0. At pH values lower than about 6.5, sulfur dioxide is released at a controlled rate during operation. Excess sulfite is consequently released from the solution, which allows the specific gravity to be maintained in protracted operation, and minimizes formation of sulfate. The solution is operable with various metallic and organic brighteners. The effects of several such brightener systems on deposit grain size, crystal orientation, leveling and porosity vs. thickness are presented
author_names: Ronald J Morrissey
title: A versatile non cyanide gold plating system
year: 1993

abstract: Ben Fa Ming She Ji Jin Tu Dian Xing Cheng Yong Fei Qing Xi Dian Jie Du Jin Yu Ji Jin Tu Dian Xing Cheng Fang Fa ,Ju Ti Di ,Ben Fa Ming Ti Gong Ju You Gua Yu Yu Ji Ban Dian Ji De Dian Ji Jie He De Tu Dian Ying Du He Tu Dian Xing Zhuang De Jin Tu Dian Xing Cheng Yong De Fei Qing Xi Dian Jie Du Jin Yu Ji Shi Yong Liao Gai Du Jin Yu De Jin Tu Dian Xing Cheng Fang Fa Gai Jin Tu Dian Xing Cheng Yong Fei Qing Xi Dian Jie Du Jin Yu De Te Zheng Zai Yu ,Han You Ya Liu Suan Jin Jian Jin Shu Yan Huo Ya Liu Suan Jin An Chuan Dao Yan Jie Jing Wen Ding Ji Jie Jing Diao Jie Ji Huan Chong Ji He Guang Liang Ji ,Ya Liu Suan Jin Jian Jin Shu Yan Huo Ya Liu Suan Jin An De Han Liang Zuo Wei Jin Nong Du Wei 1~20g/L,Chuan Dao Yan Wei Ya Liu Suan Na ,Qi Han Liang Wei 5~150g/L,Guang Liang Ji De Han Liang Wei 0.5~100mmol/L. Shang Shu Guang Liang Ji You Xuan Wei Xuan Zi Ya Feng Ji /Huo Feng De Yi Chong Huo Liang Chong Yi Shang De Hua He Wu
title: The method of forming gold bumps with a non cyanide gold plating bath and electroless gold bump
year: 2012

abstract: At present, the cyanide gold plating solution is widely used in industrial production due to the stability and excellent coating performance, but the cyanide is a highly toxic chemical, therefore non cyanide gold plating has become a development tendency in industrial production. In this research, a very stable non cyanide electroless gold plating bath composed by Sodium Gold Sulfide (Na3Au(SO3)2) complexing agents and additives was developed for electronics assembly applications. Then the additives were investigated for their concentration and action mechanism, meanwhile the operating parameters were optimized by a series of single factor's and orthogonal experiments. Finally, we assessed the bath stability and comprehensively verified the reliability of coating. The result indicates the non cyanide bath has sufficient stability and can provides the excellent Au coating to satisfy the industrial demand.
author_names: Mingqi Huang

Xiantang Li

Jianwen Xia

Xiaohai Li

Wenyu Qiu

Guoping Zhang

Rong Sun

Yong Mu
title: A conceivably stable non cyanide electroless gold plating for electronic packaging application
venue: 2017 18th International Conference on Electronic Packaging Technology (ICEPT)
year: 2017

abstract: A non cyanide gold plating bath for forming a bump is provided to control bump hardness in a range of 30~60 HV by selecting the addition amount of polyalkylene glycol and to obtain a bump made of an electrolytic gold plating film, with even surface. A non cyanide gold plating bath for forming a bump comprises alkali gold sulfites or ammonium gold sulfites as a gold source; water soluble amine as a stabilizer for the plating bath; a crystallization control agent; conductive salt 5~150 g/L consisting of sodium sulfite; a buffer agent; and polyalkyleneglycol 0.01~10 mg/L of the molecular weight 2000~6000.
author_names: yuki nakamura

koiciro inoue
title: Non cyanide gold plating bath for bump and preparation method of bump
year: 2008

abstract: A non cyanide gold pleating bath for forming a bump is provided to manufacture the bump having proper hardness and an even surface by containing a surfactant or polyalkylene glycol. A non cyanide gold pleating bath for forming a bump includes conducting salt of 5~150g/L consisting of gold sulfite alkaline salt or gold sulfite ammonium sulfate, crystal modifier, and potassium sulfite, polyalkylene glycol 1mg/L~6g/L of 200~6000 molecular weight and/or an amphoteric surfactant 0.1mg~1g/L and watersoluble amine and/or a buffer material. The bump is manufactured by processing over 5 minutes with the heat at 200~400degC after using the gold pleating bath on a wafer(1) Coat hardness of the bump is 50~90 Hv, height difference of a surface is 1.8 micron meters or less.
author_names: yuki nakamura

koiciro inoue
title: Non cyanide gold plating bath for bump
year: 2008

abstract: (Tasks) provides a gold plating bath that can be used for gold plating is formed in both the ENIG process and ENEPIG process. [MEANS FOR SOLVING PROBLEMS] As a water soluble geumyeom and a reducing agent and a complexing agent comprising, and electroless gold plating bath that does not contain cyanide to the reducing agent, formic acid or a salt thereof, and a non cyanide comprising the hydrazine flow Electroless gold plating bath.
author_names: dosiaki sibata

sayuri danaka

oda yukinori
title: Non cyanide electroless gold plating bath and electroless gold plating method
year: 2016

abstract: In order to determine optimum conditions of a cyanide free sodium gold sulfite electroless gold plating process and make its have industrial possibility,the effects of solution components and operative condition of this cyanide free electroless gold plating on coating were studied by coating thickness test and coating binding force test.The results show that an optimal condition of the process can prepare a smooth gold coating.The optimized factors are as follows: gold concentration is 1~3g/L;sodium sulfite concentration is 13g/L;molar ration of ethylenediamine and gold ion is(6~10) 1,potassium phosphate dibasic concentration is 30g/L,the pH value is 8~9,the temperature is 50~60.
author_names: Cao Jing
title: Technology Research about Non cyanide Gold Plating
year: 2008