WAFER CARRIER WITH SLOPED EDGE

• US 20110215071A1
• Filed: 03/01/2011
• Published: 09/08/2011
• Est. Priority Date: 03/03/2010
• Status: Active Grant

• Current Assignee: Veeco Instruments Incorporated
• Original Assignee: Veeco Instruments Incorporated
• Inventors: Mitrovic, Bojan, Quinn, William E., Mangum, Joshua
• Granted Patent: US 8,888,919 B2
• Time in Patent Office: Days
• US Class Current: 216/37
• CPC Class Codes: C23C 16/303 Nitrides
• CPC Class Codes: C23C 16/45563 Gas nozzles
• CPC Class Codes: C23C 16/45587 Mechanical means for changing the gas flow
• CPC Class Codes: C23C 16/4584 the substrate being rotated
• CPC Class Codes: C23C 16/4585 Devices at or outside the perimeter of the substrate support, e.g. clamping rings, shrouds
• CPC Class Codes: H01L 21/68735 characterised by edge profile or support profile
• CPC Class Codes: H01L 21/68764 characterised by a movable susceptor, stage or support, others than those only rotating on their own vertical axis, e.g. susceptors on a rotating caroussel
• CPC Class Codes: H01L 21/68771 characterised by supporting more than one semiconductor substrate

Abstract

A wafer carrier includes a body defining a central axis, a generally planar top surface perpendicular to the central axis, and pockets recessed below the top surface for receiving wafers. The body can include a lip projecting upwardly around the periphery of the top surface. The lip can define a lip surface sloping upwardly from the planar top surface in a radially outward direction away from the central axis. The body can be adapted for mounting on a spindle of a processing apparatus so that the central axis of the body is coaxial with the spindle. The lip can improve the pattern of gas flow over the top surface of the wafer carrier.

Claims

1. A wafer carrier comprising a body defining a central axis, a generally planar top surface perpendicular to the central axis, and pockets recessed below the top surface for receiving wafers, the body including a lip projecting upwardly around the periphery of the top surface, the lip defining a lip surface sloping upwardly from the planar top surface in a radially outward direction away from the central axis, the body being adapted for mounting on a spindle of a processing apparatus so that the central axis of the body is coaxial with the spindle.

2. A wafer carrier as recited in claim 1 wherein the body defines a cylindrical peripheral surface coaxial with the central axis and the lip surface joins the peripheral surface at a sharp edge.

3. A wafer carrier as recited in claim 1 wherein the body defines a cylindrical peripheral surface coaxial with the central axis and the lip surface joins the peripheral surface at a radiused edge.

4. A wafer carrier as recited in claim 1 wherein the lip surface defines a constant slope angle relative to the top surface of the wafer carrier.

5. A wafer carrier as recited in claim 1 wherein the lip surface defines a slope angle relative to the top surface of the wafer carrier, the slope angle varying as a function of radial distance to the central axis.

6. A wafer carrier as recited in claim 1 wherein the lip surface intersects the top surface at a radial distance from the central axis equal to a maximum radial extent of the pockets from the central axis.

7. A wafer carrier as recited in claim 1 wherein the lip surface intersects the top surface at a radial distance from the central axis less than a maximum radial extent of the pockets from the central axis.

8. A wafer carrier as recited in claim 1 wherein the height of the lip is about 1 mm or less.

9. A wafer carrier as recited in claim 1 wherein the height of the lip is about 0.6 mm.

10. A wafer carrier as recited in claim 1 wherein the body defines a cylindrical peripheral surface coaxial with the central axis, the peripheral surface including a re-entrant surface projecting radially inwardly toward the central axis in a downward direction from a juncture between the lip surface and the peripheral surface.

13. A processing apparatus comprising:

(a) a reaction chamber;

(b) a spindle extending upwardly and downwardly within the chamber;

(c) a wafer carrier as recited in claim 1 mounted to the spindle, the central axis of the spindle being coaxial with the spindle;

(d) a fluid inlet element communicating with the reaction chamber above the wafer carrier, the fluid inlet element being constructed and arranged to direct one or more gasses downwardly toward the wafer carrier; and

(e) an exhaust system communicating with the reaction chamber below the wafer carrier.

14. A method of processing wafers comprising the steps of directing gases downwardly onto the wafer carrier of the processing apparatus as recited in claim 13 while wafers are disposed in the pockets of the wafer carrier, and while rotating the spindle and wafer carrier about the central axis and while removing gasses through the exhaust system.

15. A method as recited in claim 14 further comprising heating the wafer carrier and wafers.

16. A method as recited in claim 15 wherein the gasses react to form a deposit on exposed surfaces of the wafers.

17. A method as recited in claim 14 wherein the flow at elevations above the top surface of the wafer carrier and near the periphery of the wafer carrier is substantially non-recirculating.

11. A wafer carrier comprising a body defining a central axis, a generally planar top surface perpendicular to the central axis, and pockets recessed below the top surface for receiving wafers, the body having a cylindrical peripheral surface coaxial with the central axis and intersecting the top surface at a sharp edge, the body being adapted for mounting on a spindle of a processing apparatus so that the central axis of the body is coaxial with the spindle.

12. A wafer carrier as recited in claim 11 wherein the peripheral surface includes a re-entrant surface projecting radially inwardly toward the central axis in a downward direction from a juncture between the top surface and the peripheral surface.