One Stop Micro

If you are dead-set on doing things a certain way, it might end up costing you a lot. Thinking out of the box helps, and a person with a wide exposure to micromachining processes can guide you.

Example

Blank glass wafers 220 microns thick need to have holes drilled in them. Sizes vary from 500 microns to 50 microns. Placement precision is liberal. The only problem is that the hole are numerous.

You send out samples to different vendors, and all of them demonstrate good cut quality and similar prices. The pricing is way beyond your initial budget, but still go with it because you have been told numerous times that drilling 50 micron holes is possible only with lasers.

After a few runs, management decides to drop the project because it is over-priced.

Analysis

You should have had the larger holes ultrasonically drilled, the smaller ones laser machined. The bigger holes take the bulk of the time in a laser process because they have t be trepanned, and being a serial process makes it even worse.

However, in an ultrasonic process, the big holes (usually down to 250 microns) are easily machined, that too in parallel. All that needs to be done is to finish the big holes, and then send it off to the laser job shop. They will then locate the holes and get the coordinates right, and then drill the smaller holes.