Method for preparing bismuth telluride alloy thin film by employing cosputtering sedimentation method

Abstract

The invention relates to a method for preparing bismuth telluride alloy membrane through a co-sputtering and sedimentation method. The invention is implemented on a magnetism control sputtering instrument, a high purity bismuth sheet is stuck on a high purity bismuth target through conducting glue, and the compound target is taken as the sputtering target material to perform co-sputtering; the single crystal silicon chip is taken as the membrane lining bottom. The invention has the technology parameters that: the bottom vacuum degree is higher than 1.0*10-3Pa, the working argon gas pressure is 0.2 to 3Pa, the target base distance is 4 to 10cm, the base sheet table is rotated for 5 to 15 circles per minute, the membrane lining bottom temperature is 100 to 300 DEG C, the sputtering power source power is 20 to 100W, and the annealing temperature is 200 to 300 DEG C. The invention has the advantages that the sedimentation membrane components can be easily adjusted by changing the size and quantity of the sticking target on the standard target material; in particular, to the sputtering compound target with larger deposited membrane component difference, and the exploration of the optimum component doping quantity, the method is simple, the feasibility is strong, the product quality is reliable, and the reproducibility is good.

Description

(1) Technical field [0001] The invention relates to a method for preparing a bismuth telluride alloy thin film, in particular to a method for preparing a bismuth telluride alloy thin film by a co-sputtering deposition method. (2) Background technology [0002] Thermoelectric devices made of semiconductor thermoelectric materials have the advantages of miniaturization, light weight, no noise, no use of heat transfer medium, and no pollution. They have great application prospects in the fields of thermoelectric power generation and refrigeration. Bismuth telluride (Bi 2 Te 3 ) compounds and their solid solution alloys are one of the earliest and most mature thermoelectric materials studied. The best thermoelectric figure of merit of bulk materials at room temperature is about 1, and most thermoelectric cooling elements currently use such materials. Due to the low thermoelectric figure of merit of the bismuth telluride bulk material, the thermoelectric conversion efficiency o...

AI Technical Summary

Problems solved by technology

However, when bismuth telluride is used as the sputtering target, due to the different sputtering rates of bismuth (Bi) and tellurium (Te), and the difference in the saturation vapor pressure of Bi and Te by 4-5 orders of magnitude, so that the sputtering deposited There is a large deviation between the composition of the film and the composition of the target; and the thermoelectric properties of bismuth telluride are closely related to the composition, so when using a bismuth telluride target to sputter and deposit a film, a film that meets the stoichiometric ratio is often not obtained, so it cannot meet production needs