Dispersion plate for flowing vaporizes compounds used in chemical vapor deposition of films onto semiconductor surfaces

A dispersion plate for evenly flowing into a processing chamber a vaporized material such as a tungsten compound during chemical vapor deposition of metal layers onto a semiconductor body, the plate comprising:

• a disc-like body having a center axis, an outer diameter, an input face, an output face, and a thickness between the faces;
• the disc-like body defining a cup-like entrance along the center axis in the input face for receiving a stream of vaporized material;
• the disc-like body defining a first plurality of passages for flow of vapor, each passage having a length and a diameter and extending radially from the entrance like the spokes of a wheel at a first inclined angle relative to the center axis from the input face to the output face;
• the disc-like body defining a second plurality of passages for flow of vapor, each passage having a length and a diameter and extending radially from the entrance like the spokes of a wheel at a second inclined angle relative to the center axis from the input face to the output face;
• the disc-like body defining a hole therethrough having a flared diameter and extending along the center axis from the entrance in the input face to the output face, the hole and plurality of passages having sufficiently large diameters to cause only low pressure drop to flow of vapor flowing through them;
• and
• a first and a second annular groove formed into the output face, the bottom of the first groove intersecting with the first plurality of passages, the bottom of the second groove intersecting with the second plurality of passages, such that streams of vapor flowing through the passages are blended to achieve a relatively even flow of vapor onto the semiconductor body and deposition of solid material on the output face is minimized.

Apparatus for processing of semiconductor wafers, the apparatus comprising:

• a processing chamber which can be maintained at sub-atmospheric pressure;
• a platform or susceptor within the chamber for holding a wafer during processing;
• and
• a dispersion plate for flowing into the chamber and onto a wafer vaporized material for chemical vapor deposition of a solid film onto the wafer, the plate comprising:
• a disc-like body having a center axis, an outer diameter, an input face, and output face, and a thickness between the faces;
• an entrance along the center axis in the input face for receiving a stream of vaporized material;
• the body defining a plurality of passages through the plate for flow of vaporized material, each passage having a length and a diameter and extending radially like spokes of a wheel from the center axis at respective inclined angles from the input face to the output face;
• and
• the body defining a hole therethrough having a diameter and extending along the center axis from the entrance in the input face to the output face, the hole and plurality of passages having sufficiently large diameters to give minimal pressure drop to the vaporized material flowing through them and to provide dispersion of flow through the plate such that vaporized material flows evenly onto a wafer surface.

Apparatus for chemical vapor deposition (CVD) of metal films onto semiconductor wafers, the apparatus comprising:

• a processing chamber which can be maintained at pressures of less than a Torr;
• a platform within the chamber for holding and heating a wafer during processing;
• and
• a dispersion plate for flowing into the chamber and onto a wafer vaporized metal compound for chemical vapor deposition of a metal film onto a wafer;
• the plate comprising:
• a disc-like body having a center axis, an outer diameter, an input face, and output face, and a thickness between the faces;
• an entrance along the center axis in the input face for receiving a stream of the vaporized material from an external source;
• the body defining a first plurality of passages for flow of vapor, each passage having a length and a diameter and extending radially from the entrance like the spokes of a wheel at a first inclined angle relative to the center axis from the input face to the output face;
• the body defining a second plurality of passages for flow of vapor, each passage having a length and a diameter and extending radially from the entrance like the spokes of a wheel at a second inclined angle relative to the center axis from the input face to the output face;
• the body defining therethrough a hole having a flared diameter and extending along the center axis from the entrance in the input face to the output face, the hole and plurality of passages having sufficiently large diameters to cause only minimal pressure drop to flow of vapor flowing through them;
• and
• a first and a second annular groove formed into the output face, the bottom of the first groove intersecting with the first plurality of passages, the bottom of the second groove intersecting with the second plurality of passages, such that streams of vapor flowing through the passages are blended to achieve more even flow of vapor onto a semiconductor wafer and deposition of solid material on the output face is minimized.