Patent ID: 7084355

Claim:
A multilayer printed circuit board comprising: an inner layer including a buried-type through hole having a side wall and a through-hole conductor formed by copper plating on said side wall, the inside of said buried-type through hole being filled with resin, said through-hole conductor having a thermal expansion coefficient of about 17 ppm/° C., and the resin in said buried-type through hole has a thermal expansion coefficient greater than that of said through-hole conductor; an outer layer formed on said inner layer; a land between said inner layer and said outer layer and connected to said through-hole conductor, an outer edge of said land being within about 0.055 mm of an edge of said multilayer printed circuit board; and a conductor layer formed on said outer layer, said conductor layer having a size and strength to prevent microcracks in said multiplayer printed circuit board when said board is heated during operation or testing, said conductor layer completely overlying said land and extending outward further than said outer edge of said land, wherein a distance from said outer edge of said land to an outer edge of said conductor layer is at least about 50 μm, and wherein said outer edge of said conductor layer is within about 0.5 mm from said edge of said multilayer printed circuit board.