John below are a number of emails on fungus that graced TechNet some time
back.
Regards
__________________________________________________
David W. Bergman, Technical Director
IPC
2215 Sanders Road
Northbrook, IL 60062-6135
847-509-9700 x340 Phone
847-509-9798 Fax
email [log in to unmask]
www http://www.ipc.org
faxback support 800-646-0089
---------------------------------------------------
On Wed, 5 Jun 1996 [log in to unmask] wrote:
> Hi everybody!
>
> I am looking for some information about reducing algae and bacterial growth
> in process baths. In the last few weeks, I've had several engineers
> propose some rather nasty chemicals they wanted to add to either gold
> baths, or photodeveloping baths to stop algae from growing. Does anyone
> else have this problem? What do you use? Do you have any concerns about
> pass-through to your POTW?
>
> I talked to some guys from DuPont at IPC Expo, and they weren't too
> concerned about pass-through. However, they were selling photochemistry
> also!! (Sorry about that, John Lott. I had to get that in.)
>
> I would appreciate any information, abuse, snide comments, etc.
>
> John Sharp
> Merix Corporation
> Forest Grove, OR Operations
> 503-359-9300 (ext. 5-4351)
> 503-359-1040 FAX
> [log in to unmask]
>
>
>From [log in to unmask] Thu Jun 6 08:08:12 1996
Date: Wed, 14 Feb 1996 07:56:01 -0500 (EST)
From: John Nelson <[log in to unmask]>
To: dhoppe <[log in to unmask]>
Cc: [log in to unmask]
Subject: Re: Fungal contamination
It's quite common to see growths in developer rinses which are mildly
alkaline and contain organics or in finishing rinses like CU-56 but I've
not seen it in acid plating rinses. The best approach I've seen is to add
a strong hypochlorite bleach to the tank once a month to kill the
bacteria and then rinse thoroughly and refill.
---------------------------------------------
While cruising the Internet, be sure to visit
our home page at http://www.automata.com
---------------------------------------------
On Tue, 13 Feb 1996, dhoppe wrote:
> Has anyone had any exposure to fungal growths in thier plating line
> rinse tanks (especially after the acid cleaner). This hyphae is quite
> hearty and nothing seems to kill it. It is not an algae. I've even
> tried glutaraldehyde, a common antifoulant used in the metal finishing
> industry, to no avail. What does anybody say?
>
> Don Hoppe Jr.
> ZYCON
> [log in to unmask]
>
>
>From [log in to unmask] Thu Jun 6 08:08:18 1996
Date: Wed, 14 Feb 96 09:23:14 EST
From: [log in to unmask]
To: [log in to unmask]
Subject: Re: Fungal contamination
Don,
I had this problem before. (Sounds like you have a good
DI system) We had to make a portable vacuum/scrub/filtration system
that we would weekly sweep/mop/scrub the rinse tanks to remove
this beast. I couldn't find a way chemically to do this (but I
also didn't have Technet's exposure either). The good thing was
that the portable vacuum could also be used to capture any
fiberglass and metal particulate that accumulated at the bottom
of the tank.
Groovy
______________________________ Reply Separator _________________________________
Subject: Fungal contamination
Author: [log in to unmask] at SMTPLINK-HADCO
Date: 2/13/96 8:34 PM
Has anyone had any exposure to fungal growths in thier plating line
rinse tanks (especially after the acid cleaner). This hyphae is quite
hearty and nothing seems to kill it. It is not an algae. I've even
tried glutaraldehyde, a common antifoulant used in the metal finishing
industry, to no avail. What does anybody say?
Don Hoppe Jr.
ZYCON
[log in to unmask]
>From [log in to unmask] Thu Jun 6 08:08:29 1996
Date: Wed, 14 Feb 1996 22:37:51 -0500 (EST)
From: [log in to unmask]
To: [log in to unmask]
Subject: Fungal Contamination
Usually the copper plate rinses are too acid for this; especially
ones with a surfactant in them. Worst I've had was in a dragout
after catalyst. Stuff wouldn't plate in acid copper but the metals
it took up sure did. Probably one of the first direct plate's in
the industry :). Lots of these things have an exterior that protects
them from oxidizers & such. I ended up using 2% peroxide, rinse,
mechanical scrubbing, more peroxide and rinse. Repeat monthly.
Don't forget to let Wastetreatment know about the oxidizer before
they see it or you may see an even uglier sight then the slimy stuff.
Ok, so there is a disadvantage to working in the balmy coastal climate.
Tom Waznis
Process Eng.
HCI Inc.
619-453-7800
>From [log in to unmask] Thu Jun 6 08:08:34 1996
Date: Fri, 16 Feb 1996 14:33:02 PST
From: Michael Barmuta <[log in to unmask]>
To: dhoppe <[log in to unmask]>
Cc: [log in to unmask]
Subject: Re: Fungal contamination
On Tue, 13 Feb 96 14:10:04 PST dhoppe wrote:
> From: dhoppe <[log in to unmask]>
> Date: Tue, 13 Feb 96 14:10:04 PST
> Subject: Fungal contamination
> To: [log in to unmask]
>
> Has anyone had any exposure to fungal growths in thier plating line
> rinse tanks (especially after the acid cleaner). This hyphae is quite
> hearty and nothing seems to kill it. It is not an algae. I've even
> tried glutaraldehyde, a common antifoulant used in the metal finishing
> industry, to no avail. What does anybody say?
>
> Don Hoppe Jr.
> ZYCON
> [log in to unmask]
Don:I've seen this same problem with acid cleaners when used in a
preclean line for dry film resist prior to pattern plate(don't know if this
is your application).Many acid cleaners contain surfactants and organic acids
when these combine with resist residue and incoming rinse water these types
of growths can occur.
One thing that has worked for me in the past was to use spent
microetch.If you are using a persulfate(potassium or sodium)based chemistry
the combination of the oxidizing potential of the persulfate and the
anti-fungal properties of the copper can knockout most of this stuff.
Fill the tank up with microetch let it sit 6-12hrs. drain and scrub
with same chemistry rinse and drain thoroughly. Good Luck.
Regards
Michael Barmuta
Staff Engineer
Fluke corp.
Everett Wa.
206-356-6076
>From [log in to unmask] Thu Jun 6 08:08:39 1996
Date: Mon, 19 Feb 96 11:56:50 EST
From: [log in to unmask]
To: [log in to unmask], [log in to unmask]
Subject: Re: Fungal contamination
In responce to you're question about fungus growth... I work in a wet process
area, and our standard procedure is a bleach treat. We use Sunny Sol 150
(sodium hypochlorite). A strong treatment with this kills most fungi in our
tanks. Also, if there is no circulation in the tanks, try a counterflow,
overflow, or pump and filter type setup...
Russ Williams
|