公开(公告)号：DE2724346A1

公开(公告)日：1978-01-05

申请号：DE2724346

申请日：1977-05-28

Applicant: IBM

Inventor： DOUGHERTY JUN WILLIAM EDWIN ,  GREGOR LAWRENCE VINCENT ,  KLEIN DONALD LEE ,  REDMOND THOMAS FRANCIS

IPC: H05K7/20 ,  F25D9/00 ,  G12B15/02 ,  H01L23/427 ,  H01L23/44

Abstract: A device for removing contaminant impurities, particularly contaminants existing at very low levels, from a liquid, including a heating element at least partially immersible in the liquid, a confinement means at least partially immersible in the liquid for maintaining a pulsating bubble of vapor of the liquid, the heating element located within the confining means, openings in the confining means to allow periodic partial escape of the vapor bubble and ingress of liquid.

公开(公告)号：DE2261120A1

公开(公告)日：1973-07-12

申请号：DE2261120

申请日：1972-12-14

Applicant: IBM

Inventor： DOUGHERTY JUN WILLIAM EDWIN

IPC: H01R12/51 ,  H05K1/02 ,  H05K1/11 ,  H05K3/42 ,  H05K3/46 ,  H05K3/36

Abstract: A multilayer printed circuit board wherein via holes, which extend from one surface to the other of one layer of the board, are arranged to be concentric with through holes, which extend from the top surface of one layer to the bottom surface of another layer. The via holes are equal in size to the clearance space which would normally surround a through hole. In the manufacturing process, the large via holes are made for individual layers of the printed circuit board. During lamination, prepreg will be extruded into the via holes. After lamination, the through holes will be drilled through the center of the via holes. The prepreg which had been extruded into the via holes will insulate them from the concentric through holes.