Semiconductor Enclosures Incorporated (SEI) is a powder to package, fully integrated HTCC technical ceramics manufacturer located in Newburyport, Massachusetts. SEI provides ceramic tape systems, ceramic substrates, multilayer ceramic substrates, metallization services, metal to ceramic assemblies, and microelectronic ceramic packaging. We specialize in variety of aluminas, ZTA, and AlN. SEI provides ceramic based products and services to customers in microwave, RF, power, Hi-Rel, military, communications, aerospace, medical, optical and industrial markets. We manufacture here in the USA with Conflict Free Minerals and RoHS compliant materials.