Posted by Dan (126.96.36.199) on August 04, 2005 at 15:09:53:
In Reply to: How are samples mounted for SRA? posted by Anonymous on August 04, 2005 at 15:07:33:
Special angled beveling blocks are anchored to the z-axis chuck with a setscrew. We use wax to attach the samples to the angled bevel blocks. We heat the block on our hot plate enough to melt a small dab of wax. (~100C) Then we remove the block from the hot plate and press the sample into the wax, squeezing any excess out so that the back surface of the sample is parallel to the top surface of the angled beveling block. The block is then placed on a heat sink to cool. Once the wax cools, it sets, anchoring the sample firmly in place and the sample is ready to bevel.
For special samples requiring no heating, we will hot wax a sacrificial piece of silicon to the block. After the block is cool, we super glue the sample to the sacrificial piece. Once the analysis is complete there is a slight amount of heating required to soften the wax and remove the sample/sacrificial sandwich. To play it safe we normally leave these types of samples mounted until after our customer reviews their data.
The bevel is created by attaching the block to a special beveling jig with a setscrew and grinding an angled surface against a diamond embedded glass surface. The glass plate is lubricated with oil to help flush the debris from the bevel. This creates a plane on the sample that is parallel to the backside of the beveling block. This makes the bevel horizontal once it is on the probe. Once the beveling is completed the sample is cleaned and attached to the z-axis chuck which can then be placed under the microscope subassembly for profiling.