Correction analysis for the deviation between vacuum furnace and material growth temperatures

To resolve a general problem that exist differences between the vacuum furnace instrument display temperature (TD, detected by thermocouple generally) and that on the substrate surface (TS) for growing thin films, we present here an effective method for measuring the real TS values as well as correcting the temperature difference between TD and TS. Concurrently, a set of heat conduction models, which is used to derive a theoretical equation for describing the relationship between TD and TS, has been well constructed. It indicates that the temperate difference ΔT (ΔT = TD - TS) increase with the decrease of chamber vacuum, while decrease with the reduction of distance between the tungsten heater and sample holder. Our calculated results based on the theoretical equation can be well agreed with the experimental data in the temperature range of 600-1000 K, but exhibit a deviation with experimental ones below 600 K. In this article, the reason for inducing the temperature deviations between experiment and theoretical calculation has been well elucidated. Our work provides a useful technique to understand the basis of temperature deviation in general heating and thermal conduction systems, at the same time, presents a simple and practicable method to correct this deviation.