Wafer maps are used in the back end of the IC manufacturing industry to annotate the die on a wafer - the annotation may indicate the die's identity, whether the die is good or bad or the "grade" of the device.
WaferMap Convert has two functions: 1) as an aid to create the layout for bump redistribution circuitry that is added to the wafer after the regular manufacturing is completed; 2) to convert a map file in one format to another format.
SINF formatted wafer map
February 5, 2018
Our initial development of WaferMap did not take into account the large number of different inputs and outputs that would be requested by our customers. It was not written in a way that made adding additional formats fast and efficient. Therefore we started work on a completely new WaferMap Convert (v2.0) that utilized a neutral database -- all incoming formats are converted into the neutral database and all outgoing formats are generated from the neutral database.
This architecture should make it faster and more efficient to add new input and output formats. However that also means that v2.0 will not yet support many of the current formats supported by V1.0.
A link to the WMap 2.0 user manual is here: WMAPConvert V2.0 User Manual.
While the basic data of a wafer map is fairly simple, foundries that provide map data (and equipment that reads map data) do not adhere to a single standardized format. This means that a software utility designed to convert map files must support a large number of different formats.
The formats currently supported by Wafermap Convert v1.0 are listed on this page: Supported Formats
If your format is not supported, please send us a sample and documentation (if needed) and we will determine whether it can be added.
WaferMap Convert v1.0 supports a number of different output formats:
We have encountered wafer maps that lack essential data needed to create a physical layout -- for example, some maps are missing the step size of the die. This information must be manually entered in order to actually produce a layout. Fortunately the step size is fairly easy to obtain and enter manually.
Most wafer map formats do not provide physical offset information -- that is, if you find the center of the array and place that at the center of the wafer, you may find that a small offset is needed in order that the good die don't fall past the wafer's boundary (or the boundary - margin.)
Over the years standard's groups have defined wafer map formats in order to help the industry exchange data more efficiently. These include:
Different wafer map formats use different terms for what may be the same property or parameter. Our glossary of terms attempts to provide definitions for the various parameters associated with wafer maps.
WMapConverter reads a number of different map file formats and produces any (or all) of the following outputs:
Standard SINF ASCII Wafer Map
WMapConverter main dialog
WMapConverter Die Dialog shows count and allows ID remapping
The user loads the wafer map file and uses the pull down to indicate what "flavor" of wafer map is to be converted. (See supported map formats ...) Once loaded the user presses the Scan ... button.
After the input file is scanned, WMapConverter displays the critical input parameters in this section. If a particular flavor of map file is missing one or more parameters, the user needs to enter those values. This might be the stepping information, the units or the position of the wafer notch. Row and Column data can always be determined by the program for a valid wafer map file.
The user selects the directory for the output file along with the "base" name. The output name will use the base name plus an extension: txt for sinf files, gds for GDSII stream and dxf for DXF file.
The user can also select the units of the output file.
Rotation - The data can be rotated clockwise about the center in increments of 90 degrees. This is useful when the foundry provides the data with the notch in one position (say on the left side) but the RDL designer works with the notch in another position (say on the bottom.)
Move - since the wafer map has no positional information the entire array is intially centered about 0,0. However it is rarely the case that the array is actually centered 0,0 on the wafer. Therefore the program allows the user to add a shift to position the array exactly where it should be on the wafer.
Unfortunately, determining the correct value of shift is not always easy given the nature of the data provided by the wafer foundry. We'll discuss ways of determining that.
Die ID Remapping
The SINF map file format has strict requirements for the ID values of each die. Other map formats don't follow these restrictions so it becomes necessary to remap those into legal SINF values. The layer dialog not only provides the user a quantity for each Die ID, it allows the user to change the ID in the converted output.For example:
Input Map --> SINF Map * --> __ X --> 01
Special Graphical Elements
The actual size of the wafer is not part of the wafer map specification. The user can enter the wafer diameter and margin and also have cross hairs drawn in the GDS and DXF Output. These additional items make it much easier to make measurements in the layout.