Databases Reference
In-Depth Information
10.4
PROCESS ANALYSIS
Once the calculations have been done on the manufactured substrates an analysis can be run on
the process to determine if the manufactured lot is “in control” and falls within the Six Sigma
quality standards. The
function determines on a point-by-point basis which
locations on the substrate (resistors) meet the Six Sigma manufacturing standards (Figure 10.7).
WithinSixSigma
Function WithinSixSigma(ByVal wksheet, ByVal row As Integer,
ByVal col As Integer, ByVal dprow As Integer, ByVal dpcol As
Integer, ByVal point As Integer) As Boolean
'Does point X satisfy six sigma criteria?
If wksheet = "ORAVG" And
SixSigmaPt
(row,
col, point) = False Then
'DO NOT ANALYZE THIS POINT
WithinSixSigma = True
Exit Function
End If
If Worksheets(SGDataSheet).Cells(dprow, dpcol).Value <=
(CellAvg(row, col) + (3 * CellDev(row, col))) And _
Worksheets(SGDataSheet).Cells(dprow, dpcol).Value >=
(CellAvg(row, col) - (3 * CellDev(row, col))) Then
WithinSixSigma = True
Else
WithinSixSigma = False
Worksheets(SGDataSheet).Cells(dprow, dpcol).Value,
(CellAvg(row, col) + (3 * CellDev(row, col)))
End If
End Function
Those points that do not conform to Six Sigma are then highlighted and colored to indicate
which positions on the substrate are not meeting manufacturing standards (Figure 10.8). In this
example, locations A1-A8 on the substrate were substandard.
The next analysis will focus only on
resistor elements within each substrate. The
goal here is to identify out-of-tolerance resistors and identify gages that contain such resistors. The
individual
function makes a determination as to whether an individual resistor on a substrate
is within allowable specifications (
WithinSpec
±
0.01%).
FIGURE 10.7
Individual resistor elements out of spec are identified.
