Repeatably Locating Image Sensor For Epoxying

[chris.hsi]

Hi there,

I've been working with these .6mm image sensors for a few months, trying various methods of handling them. My project is to epoxy this image sensor (.575mm square x .195mm) so it sits square to a hypo tube that encases the sensor cable. The hypo tube will be filled with epoxy. The cable is soldered onto 4 .13mm solder balls. I have used precision 3D printing and laser cut parts to locate these sensors in the past. I am hoping for ideas on how to square and locate such a small part for an operator to epoxy into place. I am currently thinking of using a laser cut fixture (hold the sensor square in place) mounted to a micrometer table for fine adjustment, then lowering the assembly onto the sensor. That would mean I need a precise way to hold the hype tube square.
Any concepts come to mind for squaring tiny parts?

Thanks!

 

[chicopee]

I suspect that the cross hatched part is the image sensor that you want to epoxy on the end of the hypo tube. If so then my approach would be to machine the cross hatched part (image sensor) so that it would fit over the end of the hypo tube. Allow some clearance for the epoxy or if suitable crazy glue. See the attachment for my approach to your problem.

 

[chris.hsi]

Hi there, thanks for your reply! Unfortunately I am working with pre-specced parts here, will not be machining the parts themselves. I attached the image with labels this time.

 

[DanStro]

How accurately are you looking to place this? Are you just trying to be within the 0.1 on the print or is there some other requirement that you are trying to keep?

 

[chris.hsi]

Hi DanStro, 0.1 is just for the perpendicularity spec. The other dimensions have a general 5 thou tolerance on the print, but I suspect the customer wants the sensor centered better than that.

My thoughts are that I would want some sort of small clamp to hold the sensor body so glue can be applied. Then a micrometer stage can move the sensor accurately up to the face of the hypo tube, clamped in its own fixture. There will have to be enough clearance so operators can fill the assembly with epoxy, which will be a challenge.

 

[IRstuff]

My recollection is that the typical placement accuracy of the camera die within a package is already on the order 0.15 mm, for comparably sized packages.

We've done similar things with placement, but they were based on the actual die location within the package. XY micrometer stage with clamp on the die package.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529 Entire Forum list

http://www.eng-tips.com/forumlist.cfm

 

[chris.hsi]

Thanks for the input. How did you construct the clamp to hold the camera die? I've had one precision 3D printed before, but that was for longer sensors.

 

[IRstuff]

The clamp doesn't need to be accurate, just secure; it's the positioning of the clamp with the part that needs to be accurate.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529 Entire Forum list

http://www.eng-tips.com/forumlist.cfm