High thermal conductivity aluminum nitride ceramic substrates and packages

Breakthrough technologies for achieving a whole line of AlN products for wider use in the electronics market are described. These products are: (1) plain substrates; (2) metallized substrates; (3) direct bond copper (DBC) substrates; (4) substrates for thin-film circuits; (5) substrates for thick-film circuits; and (6) cofired multilayer packages. The basic properties of AlN and problems with AlN from the manufacturing process point of view are summarized. The discussion of the breakthrough technologies needed for AlN applications focuses on four problem areas: the realization of the highest thermal conductivity by sintering, pin/lead brazing, the metallization problem for the cofired case and the postfired case, and polishing for a thin-film circuit. AlN applications and market trends are discussed.<>