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Old 09-05-2005, 02:11 PM
Grant Stockly Grant Stockly is offline
Join Date: Jan 2005
Posts: 447

<Part of the previous post>

-- [ From: Garber, Charles A. * EMC.Ver #3.1 ] --
Hi Diane,

The way this is generally done is to mill the plastic down on a grinding wheel to the point where only a fairly thin layer of plastic remains.

Then, using a plasma etcher, and a mixture of oxygen to CF4 (for example, 30% oxygen/70% CF4), whereby the oxygen etches away the plastic and the CF4 etches away the glass frit that is usually found in the plastic, you can remove the remaining plastic (package) without damaging the device itself. Different people like to use different gas ratios, of course, and that is probably a function, at least to some degree, of the concentration of glass frit in their particular plastic.

The SPI Plasma Prep II unit, as shown on URL in the world, is probably the most widely used unit for doing this type of operation. It is inexpensive and highly reliable, and requires virtually no maintenance.

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