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Conductive adhesive

G Thomas

#14648

Conductive adhesive | 19 August, 1998

Require a conductive adhesive - either isotropic or anisotrpic - which can be used for 100micron oitch devices. Must be resistant to solvents such as MEK and acetone. Cure below 150C, with possible potential for rework of the conections.

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JUSTIN MEDERNACH

#14649

Re: Conductive adhesive | 20 August, 1998

| Require a conductive adhesive - either isotropic or anisotrpic - which can be used for 100micron oitch devices. | Must be resistant to solvents such as MEK and acetone. | Cure below 150C, with possible potential for rework of the conections. MR. THOMAS, YOU'RE GOING TO HAVE A VERY VERY TOUGH TIME FINDING AN ADHESIVE THAT IS RESISTIVE TO MEK. THAT'S THE BEAUTY OF MEK. IT BREAKS DOWN THE POLYMERIC CHAIN OF ADHESIVES AND EXPIDITES THEIR REMOVAL. I DON'T BELIEVE WE'RE EVEN ALLOWED TO HAVE MEK OR ACETONE IN THE WORKPLACE IN THE U.S., ACCORDING TO OSHA. A PROCESS REQUIRING A CONDUCTIVE ADHESIVE IS, INDEED, A UNIQUE PROCESS. I'M FAMILIAR WITH THE WORLD OF CHIP AND WIRE AND FLIP CHIP SO I ASSUME ONE OF THESE IS YOUR APPLICATION? IF NOT, FIND A DIFFERENT ASSEMBLY METHOD OR ELIMINATE THE AFOREMENTIONED SOLVENTS FROM YOUR OPERATION. GREAT LAKES CHEMICAL MAKES A SOLVENT CALLED HYPERSOLVE NPB. THIS STUFF IS AMAZING (SO IT'LL PROBABLY GET BANNED SOON) LOOK INTO IT. REGARDS, JUSTIN MEDERNACH

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Manuel Cornejo

#14650

Re: Conductive adhesive | 22 August, 1998

| | Require a conductive adhesive - either isotropic or anisotrpic - which can be used for 100micron oitch devices. | | Must be resistant to solvents such as MEK and acetone. | | Cure below 150C, with possible potential for rework of the conections. | MR. THOMAS, | YOU'RE GOING TO HAVE A VERY VERY TOUGH TIME FINDING AN ADHESIVE THAT IS RESISTIVE TO MEK. THAT'S THE BEAUTY OF MEK. IT BREAKS DOWN THE POLYMERIC CHAIN OF ADHESIVES AND EXPIDITES THEIR REMOVAL. I DON'T BELIEVE WE'RE EVEN ALLOWED TO HAVE MEK OR ACETONE IN THE WORKPLACE IN THE U.S., ACCORDING TO OSHA. A PROCESS REQUIRING A CONDUCTIVE ADHESIVE IS, INDEED, A UNIQUE PROCESS. I'M FAMILIAR WITH THE WORLD OF CHIP AND WIRE AND FLIP CHIP SO I ASSUME ONE OF THESE IS YOUR APPLICATION? IF NOT, FIND A DIFFERENT ASSEMBLY METHOD OR ELIMINATE THE AFOREMENTIONED SOLVENTS FROM YOUR OPERATION. GREAT LAKES CHEMICAL MAKES A SOLVENT CALLED HYPERSOLVE NPB. THIS STUFF IS AMAZING (SO IT'LL PROBABLY GET BANNED SOON) LOOK INTO IT. | REGARDS, | JUSTIN MEDERNACH Hi Justin. Excuse my ignorance, but what reason on the earth, would prohibit the use of a solvent called NPB or whatever?. I have a very similar problem. I am investigating my notebook so I dismantled it and write down the chip it contains but two of them were covered by heat sinks glued to the chip. I guess that if the chip fails and the notebook should be serviced the heatsink shoul be removeable and the glue should be removed without damaging the IC. Could you tell me how? What solvent should I use? What adhesive should I use to replace the heatsink? Thank you Sincerely Manuel Cornejo

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Justin Medernach

#14651

Re: Conductive adhesive | 24 August, 1998

| | | Require a conductive adhesive - either isotropic or anisotrpic - which can be used for 100micron oitch devices. | | | Must be resistant to solvents such as MEK and acetone. | | | Cure below 150C, with possible potential for rework of the conections. | | MR. THOMAS, | | YOU'RE GOING TO HAVE A VERY VERY TOUGH TIME FINDING AN ADHESIVE THAT IS RESISTIVE TO MEK. THAT'S THE BEAUTY OF MEK. IT BREAKS DOWN THE POLYMERIC CHAIN OF ADHESIVES AND EXPIDITES THEIR REMOVAL. I DON'T BELIEVE WE'RE EVEN ALLOWED TO HAVE MEK OR ACETONE IN THE WORKPLACE IN THE U.S., ACCORDING TO OSHA. A PROCESS REQUIRING A CONDUCTIVE ADHESIVE IS, INDEED, A UNIQUE PROCESS. I'M FAMILIAR WITH THE WORLD OF CHIP AND WIRE AND FLIP CHIP SO I ASSUME ONE OF THESE IS YOUR APPLICATION? IF NOT, FIND A DIFFERENT ASSEMBLY METHOD OR ELIMINATE THE AFOREMENTIONED SOLVENTS FROM YOUR OPERATION. GREAT LAKES CHEMICAL MAKES A SOLVENT CALLED HYPERSOLVE NPB. THIS STUFF IS AMAZING (SO IT'LL PROBABLY GET BANNED SOON) LOOK INTO IT. | | REGARDS, | | JUSTIN MEDERNACH | Hi Justin. | Excuse my ignorance, but what reason on the earth, would prohibit the use of a solvent called NPB or whatever?. I have a very similar problem. I am investigating my notebook so I dismantled it and write down the chip it contains but two of them were covered by heat sinks glued to the chip. I guess that if the chip fails and the notebook should be serviced the heatsink shoul be removeable and the glue should be removed without damaging the IC. Could you tell me how? What solvent should I use? What adhesive should I use to replace the heatsink? | Thank you | Sincerely | Manuel Cornejo Manuel, The solvent I was referring to will probably be banned for usage in the US because of its' similarity to 1,1,1. Where 1,1,1 is an ethane based solvent, NPB is a butane based solvent. That's pretty much the only difference. I'm sure there are some other differences but I never really paid too much attention in Chemistry. You're in a bind when it comes to removing heat sinks. That's the problem with removal, it's ridiculous. Anything that will remove the adhesive will probably remove the silkscreen on the component. You're best bet is to contact the mfr. of the notebook and find out what the components are. Also, talk to the mfrs. of thermally conductive adhesives, that's what you need to put on a heat sink, and find out the best removal process. Regards, Justin Medernach

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