Patent · US Expired

Apparatus for forming diamond film

US5314540A · kind A · utility

14Cited by
5References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 23, 1992
Grant dateMay 24, 1994
Priority date
Expiry dateMar 23, 2012

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J37/32587
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

Apparatus and process for synthesizing a diamond film of high purity at a high rate. Mixture gas of hydrocarbon gas and hydrogen gas is introduced into an arc discharge to produce a gas plasma. This gas plasma is blown against a substrate to deposit diamond. A plasma current power supply is connected with a third electrode disposed above the substrate to place the third electrode at a positive potential. An electrical current is supplied into the gas plasma from the third electrode. Flow of the electrical current through the plasma promotes the decomposition of the hydrogen and hydrocarbon. A diamond film of high purity can be deposited at a high rate. The invention is characterized in that the substrate is placed at a lower potential than the third electrode or the direction of the electrical current intersects the flow of the gas plasma although the electrical current is passed through the plasma. Therefore, it is unlikely that the accelerated electrons reach the substrate, elevating its temperature. Hence, diamond of high quality can be synthesized.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.