wafer_map

Plots up a wafer map. Used in semiconductor processing and analysis.

Contents

• Features
• Installation
• Requirements
• What's it Look Like?
• Usage
  • Example
  • Nomenclature
  • Keyboard Shortcuts and Mouse Usage
• Notes
  • Current capabilities
• Changelog

Features

• Mouse and keyboard shortcuts!
• Knows SEMI M1-0302 wafer sizes!
• You can change the colors!
• Zoom in and out!
• Use it in your own wxPython apps!
• View the die grid coords, absolute coords, and die value! (but only if you use the standalone app or if your app has a status bar).
• Center your map on the wafer however you want!

Installation

Install from PyPI.

pip install wafer_map

Requirements

wafer_map requires the following non-built-in packages:

• wxPython Phoenix

  • If installing on Windows or Mac, use the wheels found at the Phoenix snapshot builds.

• numpy

• colour

and the following core (built-in) packages:

• math
• colorsys

What's it Look Like?

I know that I wouldn't want to use this if I didn't like how it looked, so here ya go. Take a look and decide for yourself if you like it.

Continuous Data being plotted as a stand-alone app:

Continuous Data as its own panel:

Discrete Data as its own panel:

Usage

I still need to fill this out in detail.

The easiest way to use this to to:

0. Import the wm_app module:

   >>> import wm_app

1. Set up your data as a list of (grid_x, grid_y, value) tuples:

   >>> data = [
   ...     (grid_x_1, grid_y_1, data_1),       # 1st die
   ...     (grid_x_2, grid_y_2, data_2),       # 2nd die
   ...     (grid_x_3, grid_y_3, data_3),       # 3rd die and so on
   ... ]

2. Call wm_app.WaferMapApp.

   >>> wm_app.WaferMapApp(
   ...     data,
   ...     die_size,
   ...     center_xy,
   ...     dia,
   ...     edge_excl,
   ...     flat_excl,
   ... )

   The input parameters for WaferMapApp are:

   • die_size: The die size in (x, y). Units are mm.
   • center_xy: The grid (x, y) coordinate that represents the physical center of the wafer.
   • dia: The wafer diameter. Units are in mm.
   • edge_excl: The exclusion distance measured from the edge of the wafer. Units are in mm.
   • flat_excl: The exclusion distance measured from the wafer flat. Units are in mm. Cannot be less than edge_excl.

3. An image should appear. Yay! Play around with it: middle-click+drag to pan, scroll wheel to zoom. See "Keyboard Shortcuts and Mouse Usage" section.

Example

There is an example file which somewhat demonstrates how to use this package. At the very least, you can run the example file and see how this wafer mapping software looks.

Navigate to the wafer_map directory in your python installtion (../Lib/site-packages/wafer_map) and run example.py in your cmd prompt or terminal:

python example.py

Example.py generates a fake data set and then displays it in 3 different ways:

1. As a standalone app. This requires only calling a single function in your code.
2. As a panel added to your own wx.Frame object. This allows you to add the wafer map to your own wxPython app.
3. As a standalone app, but this time plotting discrete (rather than continuous) data.

Nomenclature

For the entire project, the following nomenclature is used. This is to avoid confusion between a die's coordinates on the wafer (floating-point values representing the absolute postion of a die) and a die's grid location (integer row-column or x-y values that are sometimes printed on die).

• coordinate

  • Floating-point value representing the exact location of a die on the wafer. Also sometimes called 'coord'
  • The coordinate origin is the center of the wafer and the center of the FloatCanvas panel.

• grid

  • Integer value representing the printed die. Can only be mapped to a coordinate if a grid_center is defined.
  • Each grid line falls on a die's center.

• grid_center

  • The (float_x, float_y) tuple which is coincident with the wafer's center coordinate (0, 0).
  • This is the only grid value that can be made up of floats.

• row

  • Alias for grid_y.

• col

  • Alias for grid_x.

Keyboard Shortcuts and Mouse Usage

No matter if you use the standalone app or add the panel to your own wx.Frame instance, keyboard shortcuts work. I've only added a few so far, but I plan on adding more.

The panel also supports mouse controls. Middle click will pan, mouse wheel will zoom in and out.

• Home
  • Zoom to full wafer
• O
  • Toggle display of wafer and exclusion outline
• C
  • Toggle crosshair display
• L
  • Toggle legend display

Notes

This package has been released to version 1.0.0. What this means is that it should be usable in an engineering-type environment. I'm starting to use it heavily myself. It's not very customizable yet, but I don't need that capability yet. You can see the roadmap at: https://github.com/dougthor42/wafer_map/milestones

There's still a fair amount of code cleanup and refactoring to do, especially on the wm_legend.py module (as that was made last). So please do judge my coding style too harshly (though constructive criticism is much appreciated!)

Requires: wxPython

Current capabilities

1. Draw wafer outline and flat or notch.
2. Draw edge exclusion outline.
3. Draw wafer center crosshairs.
4. Accept continuous or discrete data and color accordingly.
5. Provide zoom and pan capabilities.
6. Mouse-over to display die coordinate and value
7. Legend Display for both continuous and discrete data

Changelog

See CHANGELOG.md.