Patent ID: 9493875
Filing Date: 2016-11-15
CPC Classification: C23C

Claim Text:
1. A chemical vapor deposition apparatus comprising: a chamber; a chamber lead having a gas in port configured to receive a reaction gas, the chamber lead connected to a top surface of the chamber to seal up the chamber; a shower head connected to the chamber lead, the shower head having a plurality of spray holes separated from each other for spraying the reaction gas onto the surface of a wafer in the chamber; and a protrusion protruding from a bottom surface of the shower head and surrounding the spray holes on the bottom surface of the shower head so that an induction groove is provided inside the protrusion, wherein a portion of the bottom surface of the shower head surrounded by the protrusion is flat, wherein the plurality of spray holes have a plurality of main holes and a plurality of supplementary holes, the main holes are uniformly arranged such that each of the main holes is located at each intersecting point of a virtual square-grid pattern across the shower head, and the supplementary holes are uniformly arranged separately from the main holes such that each of the supplementary holes is located at each centerpoint of the virtual square-grid pattern, wherein each of the supplementary holes has a supplementary exit hole having a taper angle and each of the main holes has a main exit hole having a taper angle that is wider than the taper angle of the supplementary hole, and wherein the main holes and the supplementary holes are arranged such that a first virtual line extended along an inner surface of the main exit hole and a second virtual line extended along an inner surface of the supplementary exit hole intersect at a collision position that is positioned between a lower end of the shower head and a lower end of the protrusion so that the reaction gas sprayed through the main holes collides with the reaction gas sprayed through the supplementary holes in the induction groove, the supplementary exit hole being positioned on the lowermost of the supplementary hole and the main exit hole being positioned on the lowermost of the main hole.