Wafer Mapping#

Wafer Mapping started being mainly used in semiconductor industry, where they are also known as wafer maps. Wafer mapping is a mapping process where the performance of semiconductor devices on a wafer are represented by a map showing their performance as a color-coded grid. The map is a convenient representation of the variation in performance across the wafer units (dies/chips), since the distribution of those variations may be a clue as to their cause.

Wafer maps are graphical representations that can hold relevant data, such as the detail about the defects found on semiconductor wafers during the manufacturing process, the measurement data or even specific material attributes that might be stored in a specific unit. These maps are generated using wafer map calculators, employing statistical analysis and visualization tools to depict defect locations and densities on the wafer surface accurately.

A wafer map spots the defective integrated circuits (dies/chips) on a silicon wafer and provides important spatial information. It enables statistical analysis by monitoring the quality of the manufacturing process through the assessment of the spatial information represented in the wafer map.

Overview#

This tutorial provides an overview of the purpose and concepts behind the following entities: Map Definition and Map. It also includes a step-by-step operational guide that walks the reader through the entire process, from creating a Map Definition in the system to creating and updating a Map instance.

Scenario#

On this scenario, it will be explored an use case where it will be created a Map Definition that graphically represents a wafer containing 1588 units (dies/chips). Since wafers have a circular shape, this will be modeled as a regular map that will have a mask file to define the wafer's circular layout.

The wafer assignment process will be performed through the creation of a Map instance, which, once created, is linked to the corresponding material. Lastly, the tutorial demonstrates how cell values within the map layers can be edited, allowing you to visualize and manage different types of data across layers.

Modeling#

This section will guide you through the required configurations and set up for the Mapping module.

Before starting the Map Definition creation, the system will require that user has pre-configured at least one value in the lookup table: MapDefinitionType.

Lookup Table Values#

For the use case that will be explored, the following configurations were previously made:

• WaferMap as a MapDefinitionType value
• nm as a Units value
• Die as a Units value

Mask File (JSON Format)#

This is the file used to create the map mask.

Modeling Notes#

• When handling a map that has regular units, but doesn't have a rectangular shape, it's necessary to upload a mask file that will act as an additional layer that shapes the map format. This is made through the translation of a binary language that indicates which map cells (units) will be populated or not.
• When creating a Map Definition that doesn't follow a regular shape, it will be necessary to upload a layout file that holds the information related with the shape of the map units - this file translates through vectorial language the shape of the map and its units.

Execution#

For this use case, when creating the Map Definition representing a wafer with 1588 dies, it is important to configure the following properties:

Table: Map Definition settings

The demonstration walks you through all necessary steps to create a new Map Definition, starting by configuring the Map Definition properties, setting up layers, and defining filters that allow you to edit the cell values for each layer.

In the second part of the tutorial, once the Map Definition has been created, you will learn how to create a Map instance, which is an executable object based on the Map Definition. This section also demonstrates how to make changes to a Map during material execution.

Execution Notes#

• The link between the Map and the material can be established either from the Map details page or the Material details page.
• After modifying cell values in any layer, the system refreshes the UI and reverts to displaying the default layer.
• Filters are displayed by default only if the Selected by Default option was enabled; otherwise, you must manually select the filter when needed.

Master Data#

This is the Master Data file used to create this model.