Method for using real-time apc information for an enhanced lot sampling engine

Abstract

A method includes passing a lot through a production process and evaluating a statistical quality of the production process. Additionally, the method includes calculating an advanced process control (APC) recipe parameter adjustment (RPA) distribution value and determining if sampling is indicated. Furthermore, the method includes, if sampling is indicated, performing a measurement process of the lot.

1 . A computer program product comprising a computer readable storage medium having readable program code tangibly embodied in the storage medium, the computer program product includes at least one component operable to:
 pass a lot through a production process;   calculate an advanced process control recipe parameter adjustment (RPA) distribution value using an advanced process controller (APC);   calculate an APC calculated process capability (Cpk) value using the APC;   communicate the RPA and the Cpk value to a lot sampling engine (LSE);   utilize the LSE to correlate the RPA and the Cpk value in conjunction with a historical Cpk value calculated by the LSE to determine if sampling of the lot is indicated; and   perform a measurement process of the lot, if sampling is indicated.   
     
     
         2 . The computer program product of  claim 1 , wherein the at least one component is further operable to:
 determine an APC RPA sampling rate based on the APC RPA distribution value;   determine an APC calculated Cpk sampling rate based on the APC calculated Cpk value; and   determine a historical Cpk sampling rate based on the historical Cpk value.   
     
     
         3 . The computer program product of  claim 2 , wherein the at least one component is further operable to:
 determine a weighted APC RPA sampling rate, a weighted APC calculated Cpk sampling rate and a weighted historical Cpk sampling rate; and   determine a lot sampling rate by summing the weighted APC RPA sampling rate, the weighted APC calculated Cpk sampling rate and the weighted historical Cpk sampling rate.   
     
     
         4 . The computer program product of  claim 2 , wherein at least one of the determining the APC RPA sampling rate, the determining the APC calculated Cpk sampling rate, and the determining the historical Cpk sampling rate comprises using configurable intervals. 
     
     
         5 . The computer program product of  claim 2 , wherein at least one of the determining the APC RPA sampling rate, the determining the APC calculated Cpk sampling rate, and the determining the historical Cpk sampling rate comprises using an S-curve. 
     
     
         6 . The computer program product of  claim 2 , further comprising determining a lot sampling rate based on the APC RPA sampling rate, the APC calculated Cpk sampling rate and the historical Cpk sampling rate. 
     
     
         7 . The computer program product of  claim 2 , further comprising determining a weighted APC RPA sampling rate, a weighted APC calculated Cpk sampling rate and a weighted historical Cpk sampling rate. 
     
     
         8 . The computer program product of  claim 7 , further comprising determining a lot sampling rate based on the weighted APC RPA sampling rate, the weighted APC calculated Cpk sampling rate and the weighted historical Cpk sampling rate. 
     
     
         9 . The computer program product of  claim 8 , wherein the determining the lot sampling rate comprises summing the weighted APC RPA sampling rate, the weighted APC calculated Cpk sampling rate and the weighted historical Cpk sampling rate. 
     
     
         10 . The computer program product of  claim 1 , wherein the calculating the APC RPA distribution value is determined according to:
   Distribution ( D )=Min((UCL−Mean)/Sigma,(Mean−LCL)/Sigma)
   
       wherein UCL is an upper control limit, LCL is a lower control limit, and Sigma is a standard deviation based on approximately ten lots. 
     
     
         11 . The computer program product of  claim 1 , wherein the determining if sampling of the lot is indicated is based on at least one of:
 a lot sampling rate;   the lot being identified as a rework lot or a send ahead (SAHD) lot;   the lot being measured in a pre-step; and   manual rules.