International Business Machines Corporation

Rudolf G Frieser

William H Ma

Rao R Tummala

Jimmie L Powell

Morton D Reeber

Gunars M Ozols

Bryant N Zingerman

Walter Fedrowitz

A cathode for reactive ion etching is provided which improves the etch rate and the uniformity of etching on the object etched. The cathode has a quartz plate with a series of recesses having disks therein of the same material as the object to be etched and a ring of that same material around the outer edge of the plate. In a preferred embodiment a cathode for etching silicon wafers has silicon disks recessed in a quartz plate at each wafer holding position and a ring of silicon around the outer edge of the plate.

Cathode for etching

The invention is a structure for improving the cooling characteristics of a silicon semiconductor device immersed in a fluid coolant. The cooling improvement is achieved by enhancing the nucleate boiling characteristics of the silicon device by initially forming lattice defects on the backside surface of the device by sandblasting and subsequently etching the damaged surface to remove the lattice defects and thereby produce an intricate surface morphology which provides nucleate boiling sites.

Nucleate boiling surface for increasing the heat transfer from a silicon

A copper oxide containing seal glass is formed by a controlled low temperature process which reduces the formation of seeds in the glass. In one embodiment the glass is prepared in two portions with the first portion containing the high melting oxides and the second portion containing the low melting oxides. The copper oxide is added to the second portion and the two portions are combined to form the seal glass at temperatures below about 800.degree.C which reduces the formation of Cu.sub.2 O crystals in the glass.

Process for preparing a copper containing sealing glass

A method for forming an oxidized chromium film on the surface of chromium metal in a controlled manner which involves the use of a permanganate solution. The chromium metal film is first subjected to a basic hydrogen peroxide solution. The chromium surface is then removed from the hydrogen peroxide solution and immersed in an aqueous permanganate solution maintained at a temperature less than about 100.degree. C. for a time preferably within 1 to 5 minutes. At this time the chromium film has been oxidized to the desired thickness depending upon the time and temperature at which the surface has been subjected to the solutions. The surface is removed from the permanganate solution and dried. Should additional thickness of chromium oxide films be desired, the surface is intermittently subjected to the permanganate solution and dried to build up the desired thickness of chromium oxide.

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Poughkeepsie, NY, United States of America

Rudolf G Frieser