High capacity epitaxial reactor
AssigneeMoore Epitaxial, Inc.
InventorGary M. Moore
Life of this patent
Estimating the term…
Abstract
A barrel epitaxial reactor having a greater batch capacity than prior art barrel epitaxial reactors which produces an epitaxial layer quality at least as good as that produced by the prior art barrel epitaxial reactors is disclosed. The batch capacity of prior art barrel epitaxial reactors is improved by increasing the reaction chamber size and increasing the radiant heat source so that a uniform temperature is maintained over a larger flat zone in the reaction chamber. Also, forced air flow from the blower of the prior art reactor is distributed so that a positive air flow is maintained along the exterior wall of the reaction chamber and consequently the wall is maintained at a uniform cold temperature relative to the temperature of the reaction chamber.
Claims42
A cold wall barrel epitaxial reactor for processing a multiplicity of wafers comprising:
- a housing, wherein said housing was designed to contain a first reactor chamber means, a first radiant energy heat source means, and a first susceptor having a flat zone of about 12 inches;
- second reaction chamber means including susceptor means having a flat zone in the range of greater than 12 inches to about 18 inches in length in a first direction wherein said second reactor chamber means is operatively mounted in said housing;
- and
- second radiant energy heat source means, operatively mounted in said housing, for providing an unsymmetrical heat energy distribution about the center of said second radiant energy heat source means in said first direction so that epitaxial layers formed on adjacent wafers in said reaction chamber have a resistivity that varies by less than approximately 10%.
A package for increasing the batch size of a barrel epitaxial reactor having a first radiant energy heat source, a voltage controller for said first heat source, a first reaction chamber with a flat zone of a first length in a first direction, means for providing gas flow, and cooling means wherein said radiant energy heat source, and said reaction chamber were contained in a housing, said package comprising:
- a second radiant energy heat source for replacing said first radiant energy heat source, said second radiant energy heat source having an unsymmetric heat energy distribution about the center of said heat source in said first direction;
- and
- a second reaction chamber having a flat zone with a length in the range of about 25% to about 50% greater than said first flat zone length, wherein said second radiant energy source and said second reaction chamber are (i) operatively connectable with said voltage controller, said means for providing gas flow, and said cooling means and (ii) operatively mountable in said housing thereby increasing the batch size of the barrel epitaxial reactor.
A package for increasing the batch size of a barrel epitaxial reactor having a first radiant energy heat source having a predetermined length, a voltage controller for said first heat source, a first reaction chamber having a wall of a first predetermined length in a first direction, first susceptor means with a flat zone of a first length in said first direction, means for rotating said first susceptor, means for controlling gas flow, and cooling means, wherein said radiant energy heat source, said reaction chamber and said susceptor means were contained in a housing, said package comprising:
- second reaction chamber means, operatively mountable in said barrel epitaxial reactor housing, having a wall of a second predetermined length in said first direction wherein the second predetermined wall length is greater than said first predetermined wall length;
- second susceptor means, operatively mountable in said second reaction chamber means, having a flat zone with a length in said first direction in the range of about 25% to about 50% greater than the length of said first flat zone;
- and
- second radiant energy heat source means, operatively mountable in said barrel epitaxial reactor housing and operatively connectable to said voltage controller, having a length greater than the predetermined length of said first radiant energy heat source, and an unsymmetric energy distribution about the center of said second radiant energy heat source means in the direction of said length, wherein, upon mounting said package in said barrel epitaxial reactor housing, said reactor has an increased batch size for processing wafers and the epitaxial thickness and resistivity uniformities of wafers in said increased batch sizes are at least as good as the uniformities of said barrel epitaxial reactor prior to installation of said package.
A cold wall barrel epitaxial reactor for processing a multiplicity of wafers comprising:
- a housing;
- wherein said housing was for another epitaxial reactor that included a first reaction chamber having a side wall of a first length, a first heat source having a first length, a first susceptor with a flat zone of a first length;
- and
- said another epitaxial reactor further including a voltage controller, means for providing gas flow and cooling means,
- a second reaction chamber, operatively mounted in said housing and operatively connectable to said means for providing gas flow, having (i) a side wall transparent to radiant heat energy and a length greater than the length of said first reaction chamber, (ii) a gas entrance, and (iii) a gas exit;
- a second heat source, operatively mounted in said housing and operatively couplable to said voltage controller, comprising a plurality of radiant heat energy lamp banks surrounding said reaction chamber wherein each lamp bank comprises a column of radiant heat energy lamps extending in a direction from said reaction chamber gas entrance to said reaction chamber gas exit so that a first end of said column is located proximate to said reaction chamber gas entrance and a second end of said column is located proximate to said reaction chamber gas exit and further wherein;
- said column has a length greater than the length of said first heat source;
- and
- said column having three heat zones consisting of a first plurality of said radiant heat energy lamps, a second plurality of said radiant heat energy lamps, and a third plurality of said radiant heat energy heat
- wherein the average energy output of said second plurality of lamps is a first level;
- the average energy output of said second plurality of lamps is a second level wherein said second level is greater than said first level;
- and
- the average energy output of said third plurality of lamps is a third level wherein said third level is greater than said second level so that said column of lamps has an unsymmetrical radiant energy field;
- susceptor means, operatively mounted in said second reaction chamber means, having a flat zone length in the range of about 25% to about 50% greater than said first flat zone length, said susceptor means comprising:
- a second susceptor having a flat zone of a second length wherein said second length is in said range;
- and
- a third susceptor having a flat zone of a third length where said third length is different from said second length and said third length is in said range;
- wherein for a batch of wafers with a specified diameter, only one of said second and third susceptors is included within said reaction chamber;
- means, operatively coupled to said cooling means, for distributing forced air flow through said second heat source onto said wall of said second reaction chamber;
- and
- means, operatively connected to said distributing means, for diverting forced air flow to a portion of said second reaction chamber wall proximate said gas entrance so that forced air flow is established along said wall of said second reaction chamber.
Dependencies are inferred from the claim text.