Method and apparatus for producing epitaxial wafer
First Claim
1. A method for producing epitaxial wafers using a single wafer processing epitaxial growth furnace, comprising the steps of:
- cleaning for removing deposit on a susceptor in the epitaxial growth furnace, wherein the epitaxial growth furnace includes a layer formation chamber which is substantially partitioned into an upper space and a lower space by the susceptor;
after the step of cleaning, performing first wafer processing for obtaining a first epitaxial wafer by mounting a first wafer on the susceptor and growing an epitaxial layer on the first wafer based on first control parameters;
without a step of cleaning for removing deposit on the susceptor in the epitaxial growth furnace after the first wafer processing, performing second wafer processing after transferring the first epitaxial wafer from the susceptor, for obtaining a second epitaxial wafer by mounting a second wafer on the susceptor and growing an epitaxial layer on the second wafer based on second control parameters set such that the second epitaxial wafer has approximately the same film thickness profile as the first epitaxial wafer;
without a step of cleaning for removing deposit on the susceptor in the epitaxial growth furnace after the second wafer processing, performing at least third wafer processing after transferring the second epitaxial wafer from the susceptor, for obtaining a third epitaxial wafer by mounting a third wafer on the susceptor and growing an epitaxial layer on the third wafer based on the second control parameters set such that the third epitaxial wafer has approximately the same film thickness profile as the first and second epitaxial wafers; and
wherein the first control parameters and the second control parameters each include a flow rate of reactive gas supplied to the upper space of the layer formation chamber and a flow rate of inert gas supplied to the lower space of the layer formation chamber, and the flow rate of the inert gas supplied to the lower space in the second control parameters is lower than the flow rate of the inert gas supplied to the lower space in the first control parameters, andwherein the first and the second control parameters are set such that a difference in epitaxial layer film thickness between the first wafer and the second wafer at a position 2 mm from each respective wafer'"'"'s edge toward a center of the wafer (ROA2 difference) is 5 nm or less over the peripheries of the first and second wafers.
1 Assignment
0 Petitions
Accused Products
Abstract
After removing deposit on a susceptor in an epitaxial growth furnace by a cleaning recipe (step S101), a first epitaxial wafer is produced by growing an epitaxial layer on a first wafer based on a process recipe A (step S102). Subsequently, a step of producing an epitaxial wafer by growing an epitaxial layer on a wafer based on a process recipe B including second control parameters set such that the epitaxial wafer has approximately the same film thickness profile as the first wafer (step S103) is repeated a plurality of times to successively produce a plurality of epitaxial wafers (step S104). The cleaning recipe, the process recipe A, and the process recipe B repeated a plurality of times are carried out repeatedly (step S105).
-
Citations
11 Claims
-
1. A method for producing epitaxial wafers using a single wafer processing epitaxial growth furnace, comprising the steps of:
-
cleaning for removing deposit on a susceptor in the epitaxial growth furnace, wherein the epitaxial growth furnace includes a layer formation chamber which is substantially partitioned into an upper space and a lower space by the susceptor; after the step of cleaning, performing first wafer processing for obtaining a first epitaxial wafer by mounting a first wafer on the susceptor and growing an epitaxial layer on the first wafer based on first control parameters; without a step of cleaning for removing deposit on the susceptor in the epitaxial growth furnace after the first wafer processing, performing second wafer processing after transferring the first epitaxial wafer from the susceptor, for obtaining a second epitaxial wafer by mounting a second wafer on the susceptor and growing an epitaxial layer on the second wafer based on second control parameters set such that the second epitaxial wafer has approximately the same film thickness profile as the first epitaxial wafer; without a step of cleaning for removing deposit on the susceptor in the epitaxial growth furnace after the second wafer processing, performing at least third wafer processing after transferring the second epitaxial wafer from the susceptor, for obtaining a third epitaxial wafer by mounting a third wafer on the susceptor and growing an epitaxial layer on the third wafer based on the second control parameters set such that the third epitaxial wafer has approximately the same film thickness profile as the first and second epitaxial wafers; and wherein the first control parameters and the second control parameters each include a flow rate of reactive gas supplied to the upper space of the layer formation chamber and a flow rate of inert gas supplied to the lower space of the layer formation chamber, and the flow rate of the inert gas supplied to the lower space in the second control parameters is lower than the flow rate of the inert gas supplied to the lower space in the first control parameters, and wherein the first and the second control parameters are set such that a difference in epitaxial layer film thickness between the first wafer and the second wafer at a position 2 mm from each respective wafer'"'"'s edge toward a center of the wafer (ROA2 difference) is 5 nm or less over the peripheries of the first and second wafers. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
-
Specification