Hollow semiconductor bodies having an outer surface composed of a doped semiconductor material and an inner surface composed of a pure semiconductor material are formed by sequential deposition from a gaseous thermally decomposable semiconductor compound onto a heated carrier member. The multi-layer hollow semiconductor bodies are directly heatable during diffusion of dopants into semiconductor elements.

A cage for low pressure chemical depositions reactors to provide for the relatively uniform deposition of silicon dioxide and phosphorus doped polysilicon along the length of a reactor by the chemical decomposition of silane. The cage is comprised of an open structure, generally surrounding semiconductor wafers supported on boats within the reactor, so as to discourage preferential deposition rates adjacent the silane inlet region of the reactor, and to encourage a more uniform distribution of the decomposable gas along the reactor length to effect more uniform deposition rates than previously accomplished. The open structure helps to quickly develop the flow along the reactor so that the flow quickly stabilizes adjacent the inlet end of the reactor and remains substantially uniform thereafter. Longitudinal alignment of the major elements of the cage provides continuous flow surfaces along the length of the reactor.

An improved tubular oven adapted for use in diffusion processing of semiconductors whose interior walls are comprised of polycrystalline silicon and whose exterior walls are comprised of phosphorous doped silicon. Block electrical contacts are located at opposed ends of such tubular oven and are comprised of conductive metal and graphite. A layer of thermal insulation circumscribes mid regions of such tubular oven.

In a refractory protective tube for the heat treatment of semiconductor components which is constricted at one end and at such constricted end is provided with a treating or working gas inlet, said tube having opposite to said gas inlet a closed end provided with a gas outlet, the improvement for the prevention of back diffusion of ambient air wherein said closed end is closed by a cover which is fastened to a holding bracket which is movably suspended from the tube.

An apparatus and method for determining the reliability of an electronic component by performing measurements which enable the ageing behavior of a parameter of that component to be predicted over time. The parameter measurements are made in-situ within the oven or environment used to control the temperature at which the measurements are made. The oven is controlled so that its temperature is kept stable, thereby permitting very high resolution measurements to be made over a relatively short time span. The temperature stability of the oven ensures that the changes of the electromagnetic parameter to be measured as a result of temperature fluctuations are negligible relative to the changes as a result of the ageing phenomena which occur in the component over time. The high resolution measurements are then used to model the parameter value as a function of time based on a deterministic model of how that parameter of the component varies over the lifetime of the component. The model is extrapolated over time to determine the reliability of the component as it ages. The result of the invention is a reliable prediction of the component's parameter value as a function of time, which enables a user or manufacturer to know when the parameter value will exceed its intended tolerance values, and either fail or cause the device in which it is incorporated to become unreliable.