METHOD AND DEVICE FOR PRODUCING NONPLANAR EPITAXIAL SILICON STRUCTURES BY WAY OF GAS-PHASE EPITAXY Russian patent published in 2006 - IPC H01L21/20 

FIELD: electronic engineering; producing nonplanar-structure microelectronic and power-electronic devices.

SUBSTANCE: proposed method for producing nonplanar epitaxial silicon structures characterized in uniform distribution of layer thickness and resistivity of charge carriers as well as dislocation density in different crystallographic directions by way of gas-phase epitaxy includes disposition of at least one semiconductor substrate in the form of hollow cylinder in vertical plane with its inner surface tightly abutting against outer surface of heating element vertically mounted in likewise cylindrical gas-phase reactor so that top and bottom parts of heating-element surface are held open. Upon sealing gas-phase reactor space dirty remnants of organic and other impurities are removed from semiconductor substrate surface and from gas-phase reactor walls by purging its space with hydrogen. Then semiconductor substrates are given gas etching with H₂-HCl mixture, volume ratio of ingredients being 20 : 1 to 200 : 1. Then semiconductor substrates are heated to epitaxial-process temperature usually ranging between 1060 and 1080 °C, and silicon epitaxial layers are deposited from SiH₄ - H₂ gas mixture onto semiconductor substrate at pressure up to 1.2 at. SiH₄ - H₂ gas mixture is supplied to reactor in volume ratio of 0.02 - 0.04 at its motion speed along reactor axis from 10 to 15 cm/s and Re criterion below 50. Reactor used for producing epitaxial silicon structures by way of gas-phase epitaxy has crystal case in the form of truncated cone installed with its small base on platform. The latter also carries vertically mounted heating element in the form of round spiral made of high-temperature alloy and placed in tightly closed cylindrical crystal casing. At least one semiconductor substrate in the form of hollow cylinder is installed with its inner surface along vertical plane immediately adjacent to outer surface of casing. Upper and lower parts of heating element surface are open. Facility for feeding gas mixture is provided in upper part of crystal cone and platform has device for gas mixture discharge.

EFFECT: enhanced uniformity of electrophysical and structural parameter distribution in nonplanar epitaxial silicon structures.

7 cl, 1 dwg