ionic residues on the surface of printed circuit assemblies

#59728

ionic residues on the surface of printed circuit assemblies | 31 August, 2009

Hi All,

As a result of equipment damage I have a problem with a cleanliness of printed circuit assemblies. One whole production batch was polluted by ionic residues because a large amount of hard water had been penetrated in the water-supply system of our spring washing machine.

I have tried to clean the printed circuit assemblies once again by a fresh cleaning solution (DI water/Axarel), unfortunately without success.

I am currently looking for a new cleaning agent or technology. I need this doing urgently. Can anyone help?

Regards, Rocko Ar

SMTDOCTOR

#59730

ionic residues on the surface of printed circuit assemblies | 31 August, 2009

You may like to contact Mike Bixenman of Kyzen Corporation at 615-831-0888 or Ravi Parthasarathy of Zestron Corporation at 703-589-1198.

#59732

ionic residues on the surface of printed circuit assemblies | 31 August, 2009

In response to your question: 3 Saponifier / non saponifier 3a Saponifiers: * Aqueous Technologies: PCB-Wash http://www.aqueoustech.com * Kyzen: XJN http://www.kyzen.com * EnviroSense: Enviro Gold #816 http://www.envirosense-inc.com 3b Non-Saponifiers: * Zestron: A200 http://www.zestron.com * Petroferm: Hydrex http://www.petroferm.com

Our questions are: * What is a "spring washing machine?" * What are the symptoms caused by "hard water had been penetrated in the water-supply system of our spring washing machine?" * How did "hard water had been penetrated in the water-supply system of our spring washing machine" occur?

#59734

ionic residues on the surface of printed circuit assemblies | 1 September, 2009

Hi davef,

In response to your questions: 1) It is a programmable washer designed for the tough demands of industrial applications. There is an integrated forced air dryer with both coarse and HEPA filters. 2) The surface of the PCB panel, the components and the solder joints are covered by a thin film which is adhered to all surfaces. 3) Still I don't know how but I hope I will find out soon.

Regards, Rocko Ar

#59738

ionic residues on the surface of printed circuit assemblies | 1 September, 2009

Rocko: While you're rooting around with the cleaner to better understand the issues with your water supply, monitor the heaters of your cleaner. We've had instances were the heater control has created "white haze" problems.

Are you sure the residue is ionic?

#59744

ionic residues on the surface of printed circuit assemblies | 1 September, 2009

Hi davef,

Thanks for the suggestion. I have inspected the heaters but I think they are OK (no visible coating, deposits, etc.). Unfortunately, I'm not sure that the residues are ionic. It was just preliminary report of the person responsible for the process.

I have made a visual inspection of the printed circuit assemblies once more and I think that the residues look more like fur and/or calcium carbonate (see the pictures). I hope that Ion chromatography analysis will reveal the truth.

Attachments:

#59755

ionic residues on the surface of printed circuit assemblies | 1 September, 2009

No, put a thermocouple on the heater and monitor the temperature during cleaning.

#59757

ionic residues on the surface of printed circuit assemblies | 2 September, 2009

Hi All,

Let me summarize the key facts and findings:

1) This is not a permanent problem. Only one production batch was affected. The cleaning solution was exchanged and now the cleaning process runs normally.

2) Probably the residues are not ionic, maybe they have been caused by fur and/or calcium carbonate.

3) The problem is not caused by equipment. The washer and the cleaning process (time/temperature cycles) were inspected and any problems have not been reported.

How can I clean the printed circuit assemblies from fur and/or calcium carbonate film if my cleaning solution had been polluted by hard water? May I use any mild acid solution? Can anyone help?

Regards, Rocko Ar

#59763

ionic residues on the surface of printed circuit assemblies | 2 September, 2009

You can determine empirically what will work. * Use ion chromatography [IPC-TM-650 2.3.28] to evaluate the residues and determine if the residues must be removed. * Use energy dispersive spectroscopy for the elemental analysis or chemical characterization of the residue.

PCBCleaning

#59766

ionic residues on the surface of printed circuit assemblies | 2 September, 2009

Advanced Cleaning Solutions is a Johnstown, PA based electronic manufacturing service provider (EMS) with more than 3,500 square feet of ESD safe facilities. Our services include precision PCB cleaning and ionic cleanliness testing/verification using either the Omega 600 or Zero Ion testers. ACS has a strong organization consisting of highly motivated personnel, modern facilities and diverse capabilities. For its size, ACS represents one of the most modern, well-equipped facilities in the region. Organizationally, ACS has the flexibility to address issues in a real time basis and a management style that encourages attention to customer requirements. ACS offers a highly skilled workforce, rapid turn time and high reliability through an established quality program; along with competitive pricing and on-time delivery.

ACS is well versed in DOD, NASA and military specifications and standards for consistency, quality and workmanship. We operate on a daily basis complying with the following requirements: MIL-STD-2000, IPC-J-STD-001 and IPC-A-610 for our workmanship standard.

ACS currently has the discipline and systems in place that are required to meet your needs for configuration management, workmanship, production surveillance, cost accounting and record keeping required to fulfill your requirements. We are confident that we have the expertise and systems in place to meet your needs. ACS is fully committed to supporting customer objectives by providing technically compliant, high quality electronic support services that offer you the best value and lowest manageable cost. Should you have any questions, please feel free to contact me.

Michael Rager-ACS PCBCleaning@yahoo.com (814)418-1852

#59769

ionic residues on the surface of printed circuit assemblies | 2 September, 2009

contacts for cleaning contractors are: * Petroferm Contract Services [www.partscleaned.com] Franklin, Ky * Aqueous Technologies [www.aqueoustech.com] Rancho Cucamonga, CA * FinePoint Precision Cleaning [www.finepointinc.com] Kokomo, IN * Austin American Technology [www.aat-corp.com] Austin, TX * PTI Industries [www.ptiwebsite.com 800-318-8438] Enfield, CT