公开(公告)号：IT1150984B

公开(公告)日：1986-12-17

申请号：IT2072480

申请日：1980-03-18

Applicant: IBM

Inventor： BUHNE JOACHIM ,  SCHAFER ROLF ,  STOFFEL AXEL

IPC: C25F3/12 ,  C25F3/14 ,  H01L21/3063 ,  C25F

Abstract: An apparatus and method for selectively electrochemically etching a surface is described. The use of the apparatus and the related method allows the establishment of etched planar surface which may be inclined with respect to the original surface. The apparatus has a cathode and multiple connectors which attach to the workpiece whose surface is to be etched. When the apparatus is operated the potential of the connectors are set so that the cathode is at least as negative as the lowest potential of the connectors.

公开(公告)号：CA1251519A

公开(公告)日：1989-03-21

申请号：CA503288

申请日：1986-03-04

Applicant: IBM

Inventor： RUH WOLF-DIETER ,  SCHAFER ROLF

IPC: B08B3/10 ,  H05K3/00 ,  H05K3/26 ,  H05H1/32

Abstract: METHOD OF DESMEARING HOLES The invention relates to a process of desmearing drilled holes in PCBs with a high aspect ratio through plasma cleaning. The plasma processing is carried out with a CF4/O2 gas mixture. By a respective selection of the CF4 contents, the method can be optimized with respect to the etching speed and uniformity through the individual drilled hole, across each individual panel and with respect to the entire panel set of the plasma reactor. It was found that an optimum is reached for these parameters with a CF4 contents of 60 Vol.% and the remainder oxygen.