Abstract: The method is used to determine whether holes etched into a dielectric layer which has been formed on a surface of a semiconductor wafer are open. A plurality of specimen holes are formed in a selected portion of the wafer simultaneously with the formation of the holes to be tested. The specimen holes are then contacted with an electrolytic probe, and the wafer is contacted with an output probe. The resistance, through the wafer, between the electrolytic probe and the output probe is determined. Since the resistance is related to the amount of dielectric material remaining in the hole, a non-destructive determination may be made as to whether the device should be subjected to additional etching.

Abstract: A semiconductor wafer is cleansed of loose foreign surface matter and chemical impurities near the surface in an apparatus which passes superheated steam over the wafer. Condensate is permitted to form and drip off the wafer. After rising above 100.degree. C the wafer becomes dry, and is removed from the apparatus and then permitted to cool.

Abstract: Instabilities in the leakage current and threshold voltage of a field effect transistor on an insulator substrate, at both room temperature and after operation at relatively high temperatures (150.degree. C), are substantially reduced by selectively doping edge regions adjacent the transverse side surfaces of the channel region of the field effect transistor, wherein the breakdown voltage of the channel-to-drain junction is substantially increased. Atoms are placed in these edge regions to provide therein a carrier concentration of at least 5 .times. 10.sup.16 atoms-cm.sup.-3 of the opposite conductivity type to that of the source and drain regions. The doped edge region extends partly across said channel region and extends fully across the side surface at the end of the source region.

Abstract: An MOS mesa transistor wherein the sidewalls of the mesa are electrically isolated from a device formed on the principal surface of the mesa, is provided. The mesa is comprised of a source and a drain which do not extend to a sidewall of the mesa. The source and the drain are surrounded by a band of semiconductor material which is a portion of the mesa and which electrically isolates the source and the drain from the sidewalls of the mesa.