Virtually all of the equipment used in the processing of semiconductors and their components receive some kind of thermal spray coating – most commonly a coating of arc-sprayed aluminium.
The purpose of the coating is to enhance the conductive (in the case of aluminium) or insulating nature of the component. Arc Spray, also referred to as metalizing or spray welding, is the most productive and economical of all thermal spray coating systems.
Arc Spray uses DC power to energize two conductive wires that emerge from the head of a gun creating an arc. The heat of the arc melts the spray substrate. Dry compressed air is introduced to the arc zone, atomizing the molten material into tiny droplets that are propelled toward the prepared part. As the droplets hit the target, they interlock, forming an extremely strong bond to each other and with the target. PTFE Group Thermal Spray Masking tape is used to strategically mask areas of the components where coating is not desired. The masking tape must withstand the abrasion of grit blasting and the abrasion of Arc Spray coatings. Once the job is complete, the tape must release easily and cleanly from the component, without leaving an adhesive residue, and leave a precise clean coating line.