Here's my thoughts:

(a) use fresh chemicals.  
(b) If you are using 30% NH4OH, cut back on the DI H2O. 
(c) once mixed, this etchant has a short shelf life (several hours at best)

I use  25 ml of NH4OH (50%), 25 ml DI H2O and about 0.5 ml H2O2 (3%). 

Are you etching PCB copper or solid Cu slugs?  




-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of [log in to unmask]
Sent: Thursday, July 13, 2017 2:44 PM
To: [log in to unmask]
Subject: Re: [TN] 1:1:1 Copper Etchant, Delineation Region of copper plating interface

Dell - Internal Use - Confidential  

That's the whole problem......   I only have the listed chemicals to work with........   

Victor,

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Tony Lentz
Sent: Thursday, July 13, 2017 2:37 PM
To: [log in to unmask]
Subject: Re: [TN] 1:1:1 Copper Etchant, Delineation Region of copper plating interface

Hello Victor,

Increasing the concentration of the hydrogen peroxide will make this solution more aggressive as a copper etchant.  The ammonium hydroxide is mainly there to aid in keeping the copper dissolved as a copper ammonium ion.   


Best regards,

Tony Lentz
Chemist / Field Application 


-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of [log in to unmask]
Sent: Thursday, July 13, 2017 1:17 PM
To: [log in to unmask]
Subject: [TN] 1:1:1 Copper Etchant, Delineation Region of copper plating interface

Fellow TechNetters:

   Is there any possible way to make the above stated etchant STRONGER/AGGRESSIVE:   Here are the chemicals:   Perhaps by varying the volume of one of the three constituents.

1   -      Ammonium Hydroxide, 28.0 - 30.0%
1   -      Hydrogen Peroxide, 3%
1  -       Deionized water

Victor,