Parylene deposition apparatus including dry vacuum pump system and downstream cold trap

摘要

Chemical vapor deposition apparatus is provided for the quick and efficient deposition of Parylene AF4 onto silicon wafers in the production of semiconductor chips. The apparatus includes an oilless, dry vacuum pump connected rierctly to the deposition chamber, and a liquid nitrogen cooled cold trap connected to the outlet of the vacuum pump. The apparatus further includes a vacuum by-pass assembly wherein a high-conductance vacuum outlet is utilized to quickly reduce pressure in the chamber system and a low-conductance vacuum manifold outlet is utilized to maintain vacuum flow during the deposition procedure.