Device and method of preparing n-type doped diamond through microwave plasma-hot filament composite chemical vapor deposition

Abstract

The invention provides a device and method of preparing n-type doped diamond through microwave plasma-hot filament composite chemical vapor deposition. The device comprises a microwave plasma source system, a hot lamp filament reaction chamber improvement system, a vacuum pumping system and a tail gas treatment system. The microwave plasma source system comprises a microwave source, a three-screwimpedance tuner, a waveguide mode converter, an antenna unit, a waveguide tube and a quartz window. The waveguide mode converter is connected with the microwave source through the three-screw impedance tuner. The hot lamp filament reaction chamber improvement system comprises a resonant cavity, a gas inlet hole, a deposition platform, a plasma, an inert gas hole, a water-cooling channel, a graphite lining, hot lamp filaments, a mirror plane steel plate, partitioned cooling pipes and a gas outlet hole. The waveguide tube is connected with the resonant cavity through the quartz window. The device provided by the invention integrates an MPCVD device and an HFCVD device, adopts the microwave source as a reaction heat source and the hot lamp filament as an annealing heat source to cooperate with the graphite lining to maintain the annealing temperature and improves the preparation efficiency and quality of the n-type doped diamond.

Description

technical field [0001] The invention belongs to the technical field of single crystal diamond film growth, and in particular relates to a device and method for preparing n-type doped diamond by microwave plasma-hot wire composite chemical vapor deposition. Background technique [0002] Diamond film has high hardness, high strength, good thermal conductivity, small thermal expansion coefficient, excellent optical properties, high chemical stability, strong radiation resistance, fast sound propagation speed, good dielectric properties, wide transmission band, and wide band gap Large, small dielectric coefficient and other advantages. Therefore, it is widely used in high-power semiconductor devices, high-power microwave windows, infrared optical window materials and other fields. Among them, n-type diamond has higher carrier mobility and can realize n-type conductivity at room temperature, which is also the key to the development of bipolar devices. Phosphorus is the only ele...

AI Technical Summary

Problems solved by technology

Generally, MPCVD has the advantages of high plasma density, no discharge electrode pollution, and good controllability, but its temperature control performance is slightly inferior to that of HFCVD.

And its common substrate cooling method will also affect the substrate temperature uniformity, thereby reducing the diamond quality

At the same time, the hydrogen element in n-type doped diamond will also combine with phosphorus element in the form of phosphorus-hydrogen bond, which will passivate the impurities in the diamond and reduce the conductivity

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