DLOG High-Performance Parametric Charts Guide (Histogram · Trend · Box Plot · Scatter · Pareto · CDF · Multi-Site Delta & ANOVA)

OVERVIEW

1. Overview & Chart Navigation

Select chart type, test item, and value range to update the chart and statistics instantly. Clicking any parameter in the Tests (Cpk) sidebar jumps directly to that test, with failing items highlighted in red.

DLOG Chart Screen Layout — **Figure 1. Chart Screen Layout** — ① Chart Type ② Test Item ③ Value Range ④ Density ⑤ Log ⑥ Filter/Find ⑦ Main Canvas ⑧ Statistics ⑨ Cpk List

Chart Types: Histogram · Trend · Box Plot · Scatter Plot · BIN Pareto · CDF / Probability (selected test remains active across types)
Value Ranges: Auto (P1~P99) · Full (Min~Max) · Spec Limits · Manual...
Filter / Find: Ctrl + F to search by test name or test number
Right-click Point: Pins part info card with direct links to Table · Record · Wafer

HISTOGRAM

2. Histogram — Distribution & Cpk

Displays measurement distributions with Gaussian fit curves, mean, ±σ, and spec limits (LL/HL). Out-of-spec samples are highlighted in red bars.

Histogram View — **Figure 2. Histogram** — The right-hand panel displays Cpk, Cp, Est ppm, and Anderson-Darling normality p-value.

Cpk Color Coding: 3 tiers (Pass / Warn / Fail) with default thresholds at 1.00 / 1.33 (customizable in Main Options). If the Normality (AD) p-value is below 0.05, the normality assumption is rejected; inspect Box Plot or CDF instead. The Log scale button is available for Histogram and CDF when all values are strictly positive.

TREND

3. Trend — Time-Series & Drift Tracking

Plots measurement values in the exact chronological sequence of die testing to detect drifts, thermal warm-up, and sudden outliers.

Trend Chart View — **Figure 3. Trend Chart** — Mean line, +3σ band, and HL limit. Out-of-spec points are highlighted in red (Fails).

Sites: Per-site color coding · Fails: Highlight out-of-spec samples · Gaps: Break lines across idle periods · MovAvg: Rolling moving average
WECO: Western Electric control chart rules (R1~R4). Click to cycle: Off → 2x → 3x → 1x. For multi-site setups with natural channel spread, 2x or 3x avoids false alarms.
DPAT (trend): Overlays adaptive Part Average Testing bands recalculated per wafer (blue), site (orange), or lot (purple).
Double-click after zooming with the mouse wheel resets back to the initial view.

BOX PLOT

4. Box Plot — Quartiles & Outliers

Presents the 5-number summary: median, interquartile range (IQR), whiskers, and outliers on a single unified canvas.

Box Plot View — **Figure 4. Box Plot** — Box = Q1~Q3, Bold Line = Median, Green Diamond/Dashed = Mean, Red Dots = Outliers beyond whiskers.

The statistics panel displays Median, Q1, Q3, IQR, Whisker bounds, and Outlier counts. Right-click any outlier dot to pinpoint the die directly on the Wafer Map.

SCATTER & CORRELATION

5. Scatter / Correlation Analysis / 3D

Examine bivariate relationships with regression lines, and inspect all pairwise correlation coefficients across the entire datalog via an interactive heatmap.

Correlation Matrix View — **Figure 5. Correlation Analysis** — Correlation coefficient heatmap, scatter plot with regression line (r, R², slope), and Top correlations ranking table.

Pearson: Linear relationship strength · Spearman: Rank-based (robust against extreme outliers)
Pairs with |r| ≥ 0.95 are flagged as Duplicate test, identifying candidates for Test Time Optimization (TTO).

3D Scatter View — **Figure 6. 3D Scatter (Dedicated 3D View)** — Simultaneously view 3 tests mapped to X, Y, and Z axes. Left-drag to rotate, right-drag to pan, wheel to zoom, double-click to reset.

BIN PARETO

6. BIN Pareto — Defect Ranking

Ranks failing BINs by occurrence count alongside cumulative contribution curves. No specific test parameter needs to be selected.

BIN Pareto View — **Figure 7. BIN Pareto** — Bars = Defect count and % per BIN, Line = Cumulative percentage (right axis). The sidebar lists BIN descriptions and shares.

The top 15 BINs are displayed individually, with remaining ones grouped into an Others bar. Cross-reference top fail modes with the Wafer Map BIN tab to inspect spatial defect clusters.

CDF / PROBABILITY

7. CDF / Probability — Distribution Tails

Plots the cumulative proportion of samples falling below each measurement threshold. The dashed curve represents the theoretical normal distribution, exposing tail anomalies and skewness where curves diverge.

CDF View — **Figure 8. CDF / Probability** — Extended tails reaching beyond the HL limit before reaching 100% reveal latent outlier dies that exceed upper bounds.

Subtle outlier dies that are virtually invisible on low-frequency histogram bars stand out clearly at the extremes of the CDF S-curve.

GROUP & SITE

8. Group Analysis (ANOVA) & Multi-Site Delta

Compare variances across sites, temperatures, lots, or tester revisions, and diagnose hardware imbalances between parallel test channels.

Group Analysis View — **Figure 9. Group Analysis** — Compare groups via Box, Hist, or Quantile plots, with One-way ANOVA (F, p-value, Eta²) and Tukey HSD post-hoc test results displayed at the bottom.

Multi-Site View — **Figure 10. SITE** — Per-site yields, BEST/WORST SITE spread, and ranking of tests by site variance (TEST MATRIX). Double-click a site number to isolate its data.

When p < 0.05 and Eta² ≥ 0.05, the variance reflects an actionable group difference. (With large sample sizes, p-values can be tiny even for negligible deltas.)
STDF Site 255 conventions (representing ALL SITE summaries) are handled intelligently via the SITE 255 on part records setting in Main Options.

EXPORT

9. Export & Reporting

Export CSV saves raw data and statistics of the active chart, while the Report Generator incorporates selected chart snapshots into formal reports. To overlay distributions from multiple files, use the Overlay tab in the Compare view.

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