Canyon Materials, Inc. - Custom Photomask Fabrication

Custom Photomask Fabrication

    RE:  Data Needed for Custom HEBS-Glass Masks

    Dear Canyon Materials, Inc. Customer,

    To facilitate the preparation of the necessary data that CMI needs to make you a customized HEBS-Glass gray scale photomask, we recommend the following:

     (1)  Customers need to first determine the relationship of developed photoresist thickness with optical densities in a HEBS-glass plate.  This can be accomplished by using a HEBS-glass calibration plate.  Please read the CMI info sheets, "Why Use a HEBS-Glass Calibration Plate" and the description of the HEBS-Glass Calibration Plate that is most suitable for your application (HEBS5, I85B, or 3Q3BL).  Another CMI info sheet, "The Photoresist Analog Transfer Scheme for HEBS-Glass Photomasks" is useful to establish your photolithographic process.

    (2)  Next, a GDSII data file of your desired mask needs to be prepared.  CMI offers the services of creating your GDSII files for the following types of mask patterns: gratings and microlens arrays. If your mask pattern is composed of mainly these types, you can send us a drawing of your design specifications and we will work with you to prepare a GDSII file that meets your particular specs. Please also review CMI Product Information No. 01-88, page 7 of this document in particular.

    Otherwise, we need to receive a GDSII data file of your mask pattern from you together with the drawing of your mask layout.

    (3) Also, send us the optical density values corresponding to the desired gray levels.  These optical densities should have been determined in the previous step with a calibration plate.

    Once we have received the above described information, we can make a firm quotation. The cost of fabricating an HEBS-glass customized gray scale mask depends on the e-beam write time and data fracture time.  The e-beam write-time depends on a number of factors including the number of gray levels and the size of the mask pattern.  We fracture the GDSII data files that our customers give us into primitive shapes that the e-beam writer can write.  The time it takes to fracture GDSII data files into primitive shapes depends on a number of factors including the size of the repeating unit.  When there is no repeating unit, the entire pattern has to be fractured and the fractured BPD data files could be more than a gigabyte for a 0.25" X 0.25" pattern.

    We hope this helps to clarify the necessary steps involved in ordering a custom-designed HEBS-glass gray scale photomask.  Good communication of design and layout parameters is important so we encourage much correspondence with customers during this process.  At any point in the process, we would be happy to offer our assistance and feel free to contact us if further clarifications are needed.

Back to CMI Home
Company | Technology | Products | Online Help | Contact