In this lesson

The charts in Insights answer the common questions. When yours is different, you can build the chart yourself. This lesson shows how to make a plot, keep it, and use it again on the next lot.

• Build your own charts in the plot editor
• Keep them, export them and reuse them on the next lot
• Read a run of tests as a sweep curve

Examples

The quickest way to start is to look at examples. On the sample lot, the My plots | Examples switch shows one or the other, never both. Examples draws one plot of each chart type the lot can show, chosen from the lot's own data. Each is marked Example, because it is not yet yours. + New plot opens a scatter already set to the lot's first two tests.

Keeping examples

Add to my plots on one example keeps just that one, and its button then says In your plots. Add all keeps every example you do not have yet and takes you to My plots, with an Undo that removes only what it added. Under each plot, the how to read this link opens the guide section for that kind of chart.

Edit, Duplicate, Delete

Each card has three buttons: Edit changes the plot, Duplicate copies it so you can try a variation, and Delete removes it. Delete can be undone straight afterwards. Changes in the editor are drawn at once and kept as you make them, so there is no save button to forget.

Chart types

Pick the type that matches your question. There are ten, and each takes different fields: a histogram takes one set of values, a box or bar takes categories. Sweep reads a run of tests as a response curve: choosing it swaps the fields for a series form (see Sweeps, at the end of this lesson), and choosing another type brings the plot's own fields back.

Group by or Compare by

There are two ways to split the data, and they work at different levels.

• Group by pools whole wafers by a wafer field, for every chart
• A plot's Colour and Categories can also split dies: by ring, bin, site or a pass/fail test
• A ring is never a Group by choice: every wafer has dies in every ring

More settings

The editor has more settings than you will need at first. These are the ones people reach for.

• Filter: keep only the dies that meet conditions
• Panels: one small plot per value of a field; a Columns control above them, or the keys 1 to 5 while the pointer is over the plot, sets how many sit side by side
• Fit line: least squares, or orthogonal for two measures of one thing
• One mark per: a point per die or per wafer

Many tests, many groups

For bigger questions, the editor can combine several tests or nest groups.

• Several tests… puts a list or range of tests in one plot; Rescale values puts them on one scale (to limits, or as z-scores)
• In ranges cuts a number into bands, such as Idsat deciles
• + Add a level nests categories, such as wafers inside each split

Reading against limits and totals

A few settings help you judge data against a target.

• What-if limits draw proposed limits on a histogram and say how many dies would change
• Colours: stacked, 100%, or each colour's share, to compare groups of different sizes
• Cumulative line turns a bar sorted largest first into a pareto

A plot's filter and the page filter

You can filter in two places, and they combine.

• Filter… in the toolbar narrows every view, and is not saved with a plot
• A plot's own Filter is saved with it and narrows that plot only
• A plot shows the dies that pass both; neither changes the other

Suggestions in the JSON

You do not have to remember the keys.

• Suggestions open as you type, after a comma or a brace, or with Ctrl+Space
• They offer the keys, the lot's tests and fields, and the values a field takes
• A change is drawn at once, and Ctrl+Z undoes the last one

Export, import, delete all

Export plots… writes every plot to a file and Import plots… adds the plots of such a file, so a set can move to a colleague or another machine. Delete all plots… asks first.

Undo

Right after deleting, Undo brings the whole list back.

A run of tests as a curve

Some test programs measure the same thing at a series of levels, such as a current at a run of voltages, with one test for each level. Read one test at a time, and the run is dozens of numbers. Read as a curve, it is one shape. The Sweep chart type draws that run of tests as one curve.

These slides use SWEEP-LOT-06 and its definitions file from lesson 09. Its plots file is on the sample files page.

Import plots…

Import plots… reads a plots file and adds its plots, which is a quick way to start from someone else's setup. SWEEP-LOT-06's plots file brings two sweeps. Each line is the median across the dies, with a shaded band from the 10th to the 90th percentile.

A sweep remembers its tests' names

A sweep is saved with the names of its tests. If a later lot uses the same test numbers for other measurements, the sweep does not draw them and says so on its card, instead of drawing another quantity as the same curve.

Recap

• My plots are recipes, redrawn on the next lot
• The editor offers ten chart types, Sweep among them; X, Y and Colour take tests, die fields or wafer fields
• Export plots… keeps a copy; Undo brings back a delete for ten seconds
• A sweep reads a run of tests as a curve and measures where two curves cross

Next, the wafers that do not look like the usual ones.

More in the wafer map guide