this invention relates to an apparatus and methods for forming polymeric devices , especially fluidic or microfluidic devices used as conduits for controlling fluid flow . such devices have important applications in chemistry and biology including immunoassays , enzyme assays and cell separation processes . the invention claims the use of fixed - temperature heating of thermoplastic resin in combination with vacuum and low pressure on the tool in order to rapidly produce good quality devices . the combination of features claimed in the invention is important because it enables simple , lightweight , economical equipment to be constructed to fabricate useful polymeric devices .