A system to imprint patterns on impressionable materials by generating a pressure differential within an imprinting chamber by creating a substantial vacuum in an imprinting area is provided. This system can be used to create conductive traces in a substrate onto which integrated circuit chips and dies can be mounted to create semiconductor packages. A low pressure line evacuates air from a material receiving area of a vessel creating a pressure differential across pistons in the vessel to thereby causing the pistons to press microtools into impressionable material layers. The low pressure line helps the microtools conform to any thickness variations in the imprinted material and prevents air pockets from developing between the microtool and the imprinted material.