Abstract: A method of diffusing dopant material into the crystal surfaces of silicon crystal slices which comprises placing the dopant material in the form of wafers between the adjacent major faces of each of a stack of silicon crystal slices, clamping said slices and wafers together as an assembly within a refractory boat so that the crystal slices are in substantially parallel vertical disposition with their entire facing surfaces covered by dopant material and thereafter introducing the boat and the assembly into a zone of high temperature wherein the dopant material is simultaneously diffused into the major faces of the silicon crystal slices. Other arrangements of silicon crystal slices and dopant wafers of the same or different materials can produce slices diffused on both sides with the same dopant or with a different dopant material on each side.

Abstract: An adapter for use with a coaxial activating syringe balloon catheter assembly is provided with a simplified slide valve which permits a precise amount of fluid to be introduced into the balloon and held therein. The fluid is injected by means of a metering syringe which can thereafter be removed without deflating the balloon. A simple longitudinal movement of the adapter will release the fluid pressure in the balloon for deflation when desired.

Abstract: A balloon catheter having a flexible tubing containing a plurality of lumens and an inflatable balloon adjacent its distal end is connected to a coaxial unit incorporating a syringe at its proximal end. The syringe applies fluid through at least one of the lumens to inflate the balloon. Other lumens are connected to fluid sources or electrical leads through the coaxial unit for diagnostic or medicinal purposes. Visual means carried by the syringe indicate balloon failure.

Abstract: A method of applying a boron dopant to silicon slices which comprises applying a dopant solution to the faces of each slice, packing a plurality of slices adjoining each other in a quartz boat and inserting the boat slowly into a tubular furnace. The boron surface of each slice is covered with alumina powder to eliminate sticking. After heating at 1350.degree. Celsius for four hours the slices are slowly pulled out of furnace.