Search NASA⌕ Search

Engineering topics

Hubert, James A.

Publications and source records attributed to Hubert, James A..

Displacement Compensation of Temperature Probe Data

Analysis of temperature data from a probe in a vertical Bridgman furnace growing germanium crystals revealed a displacement of the temperature profile due to conduction error. A theoretical analysis shows that the displacement compensation is independent of local temperature gradient. A displacement compensation value should become a standard characteristic of temperature probes used for temperature profile measurements.

Welch, Christopher S.↗

Comparison of melt-solid interface position by radiography and temperature measurement in a vertical Bridgman furnace

The melt-solid interface position was measured during the Bridgman growth of germanium by both temperature profiling and by X-ray imaging. The temperature field of the ampoule, growth material and measurement thermocouples was analyzed by means of numerical analysis. It is shown that both the temperature shift and the discontinuity in temperature gradient is a function of the imposed thermal field and the thermal properties of the thermocouples.

Hubert, James A.↗