Gridded susceptor
AssigneeASM America, Inc.
InventorsTony J. Keeton, Zachary L. Lutz
Life of this patent
Estimating the term…
Abstract
Susceptor designs are provided for controlling damage to wafers, particularly during cold wafer drops-off on a hot susceptor. The designs include axisymmetric grid designs, such that thermal gradients are symmetrical in the circumferential (θ) direction and the same traversing any particular radial line. The grids are preferably arcuate and each have the same surface area. In one embodiment an outer zone is asymmetrically designed to induce predictable wafer curling in a saddle shape.
Claims43
A grid patterned susceptor, comprising:
- a circular susceptor face;
- and
- a grid pattern on the face of the susceptor configured with a plurality of arcuate grids each having substantially the same surface area.
A grid patterned susceptor, comprising:
- a susceptor front face;
- at least two low thermal conductance areas on the susceptor face;
- and
- two high conductance areas, each high conductance area being located between two low conductance areas, the high conductance areas being configured to have higher conductive heat flux paths relative to the low conductance areas.
A method of controlling damaging effects of wafer warping during fabrication, the method comprising intentionally warping a wafer during wafer drop-off onto a wafer holder, which is hotter than the wafer upon drop-off, in order to direct the warping of the wafer to a predicted, warped shape.
A method of fabricating wafers, the method comprising consistently warping each wafer in a wafer batch, so that each, during drop-off onto a wafer holder which is hotter than the wafer, wafer warps into substantially the same shape relative to other wafers in the batch.
A method of fabricating a circular susceptor comprising:
- building a gridded susceptor comprising a first material coated by a second material;
- and
- forming arcuate grids having substantially equal surface areas on the front face of the susceptor.
Dependencies are inferred from the claim text.