Data preparation includes all of the steps that are required to insure that data is ready for the write tool.
Of the steps listed below, some are optional.
- Digitizing – This is the process of creating new data and editing that data in a graphic format.
- Sizing – In some cases it may be necessary to size the customer’s digitized data. Sizing consists of globally increasing or decreasing the size of each individual feature in the data file. This sizing can be done in one axis only (X or Y), or in both axes simultaneously (X & Y).
- Scaling – While not a common procedure, it is possible to scale the entire data file larger or smaller.
- Design Rules Check (DRC) – Certain parameters can be programmed that will allow the intermediate data to be checked to insure that rules or parameters have not been violated. An example of a common DRC is a minimum space check, in which the data is searched to be sure that no digitized pattern is closer to another pattern than a distance that was pre- assigned at the beginning of the process.
- Area Calculation – This process calculates the percentage of the total area that is digitized pattern.
- Data Rotation – In some cases it may be desirable to rotate the data file 90 degrees so that the exposure beam is sweeping in a certain direction in relationship to the pattern data so that the best feature edge quality and feature size is maintained.
- Photomask Prep – This includes adding data to the supplied intermediate data, such as text, titling, fiducials, and process control patterns (PCP’s).
- Data editing – This is the process of fixing data errors or making customer- requested changes. Usually the maskmaker will not make changes or corrections to the customer-supplied intermediate data file without first securing the customer’s permission. In most cases it is desirable to have the customer make corrections or changes themselves and then provide the maskmaker with a new data file. By so doing, the customer is assured that they are in possession of the latest revision of the data.
- Data Fracturing – This is the process in which the intermediate data (GDSII, DXF or CIF) is converted to the specific data for the write tool (MEBES or LIC).
- Exclusive-OR (XOR) – In this process the fractured data is compared to the intermediate data, anomalies are reported and, in some cases repaired if desired. The types of errors that can be detected with this routine are off-grid patterns, data dropped during fracturing, data changed during fracturing.
Optical pattern generator format.