{"id":3646,"date":"2026-08-09T23:58:14","date_gmt":"2026-08-09T15:58:14","guid":{"rendered":"https:\/\/blog.zengqq.com.cn\/?p=3646"},"modified":"2026-08-09T23:58:15","modified_gmt":"2026-08-09T15:58:15","slug":"how-to-use-dose_dat-caculate-pcomp","status":"publish","type":"post","link":"https:\/\/blog.zengqq.com.cn\/?p=3646","title":{"rendered":"How to use Dose_dat Caculate Pcomp"},"content":{"rendered":"\n

Overview<\/h2>\n

The dose.dat<\/code> file can be used to verify whether the pressure compensation value is accurate for production wafers in Axcelis ion implantation systems [1]. This technique allows process engineers to calculate and optimize PCOMP values through data analysis rather than solely relying on experimental trial methods.<\/p>\n\n

Step-by-Step Procedure<\/h2>\n\n

Step 1: Data Preparation<\/h3>\n

Extract the following two key parameters from the dose.dat<\/code> file generated during implantation into photoresist-coated wafers [1]:<\/p>\n\n\n \n \n \n \n \n
COLUMN<\/th>\n DESCRIPTION<\/th>\n SOURCE<\/th>\n <\/tr>\n <\/thead>\n
Disk Faraday Current (Imeasured<\/sub>)<\/td>\n The measured beam current readback value recorded by the disk faraday cup [1]<\/td>\n dose.dat file<\/td>\n <\/tr>\n
IG3 Pressure Reading (P)<\/td>\n Vacuum pressure reading from Ion Gauge 3 located in the end station [1]<\/td>\n dose.dat file<\/td>\n <\/tr>\n <\/tbody>\n<\/table>\n\n

Create two new calculated columns:<\/p>\n

    \n
  • Natural logarithm of the disk faraday current: ln(Imeasured<\/sub>) [1]<\/li>\n
  • Normalized IG3 pressure value P (in appropriate units) [1]<\/li>\n<\/ul>\n\n

    Step 2: Create Scatter Plot<\/h3>\n

    Using spreadsheet software or data analysis tools, plot your processed data as follows [1]:<\/p>\n

      \n
    • X-axis:<\/strong> End station vacuum pressure (P, from IG3 gauge) [1]<\/li>\n
    • Y-axis:<\/strong> Natural logarithm of beam current ln(Imeasured<\/sub>) [1]<\/li>\n
    • Chart Type:<\/strong> Scatter plot to show individual measurement points during the implantation cycle [1]<\/li>\n<\/ul>\n\n

      Step 3: Linear Fitting to Extract k-Factor<\/h3>\n

      Fit a straight line through your plotted data points using linear regression. The slope of this fitted line represents the pressure compensation coefficient k<\/em> [1].<\/p>\n\n

      Mathematical Foundation<\/h4>\n

      The underlying physics is described by the following pressure compensation formula for standard Axcelis systems [1]:<\/p>\n\n

      \n

      Iactual<\/sub> = Imeasured<\/sub> \u00b7 e(k \u2212 P)<\/sup><\/p>\n<\/blockquote>\n\n

      Taking the natural logarithm of both sides transforms this into a linear equation:<\/p>\n\n

      \n

      ln(Iactual<\/sub>) = ln(Imeasured<\/sub>) + k \u2212 P<\/p>\n<\/blockquote>\n\n

      Where:<\/p>\n\n\n \n \n \n \n \n \n \n
      SYMBOL<\/th>\n DESCRIPTION<\/th>\n SOURCE<\/th>\n <\/tr>\n <\/thead>\n
      Iactual<\/sub><\/td>\n Pressure-compensated beam current (appears as pcompI<\/code> in the Dose.dat file) [1]<\/td>\n Formula derivation<\/td>\n <\/tr>\n
      Imeasured<\/sub><\/td>\n Raw measured beam current from disk faraday readback [1]<\/td>\n dose.dat column “diskI”<\/td>\n <\/tr>\n
      P<\/td>\n Pressure reading from IG3 ion gauge [1]<\/td>\n dose.dat pressure columns (e.g., end_hcig)<\/td>\n <\/tr>\n
      k<\/td>\n Linear fitting slope = Pressure Compensation Factor [2]<\/td>\n Calculated result<\/td>\n <\/tr>\n <\/tbody>\n<\/table>\n\n

      Step 4: Convert k-Factor to PCOMP Recipe Value<\/h3>\n

      After obtaining the k-factor from your linear fit, convert it to the actual recipe parameter using this formula for standard pressure compensation mode [1]:<\/p>\n\n

      \n

      PCOMP = 100 \u00d7 (ek<\/sup> \u2212 1)<\/strong><\/p>\n<\/blockquote>\n\n

      Important Technical Notes<\/h2>\n\n

      Pressure Compensation Modes<\/h3>\n\n\n \n \n \n \n \n
      MODE<\/th>\n COMPLEXITY<\/th>\n RECOMMENDATION<\/th>\n <\/tr>\n <\/thead>\n
      Standard PCOMP<\/td>\n Linear fitting is valid [1]<\/td>\n Use above formula<\/td>\n <\/tr>\n
      Gamma Pressure Compensation<\/td>\n Fitting becomes significantly more complicated due to non-linear response<\/td>\n Requires alternative methods or vendor consultation [1]<\/td>\n <\/tr>\n <\/tbody>\n<\/table>\n\n

      Physical Mechanism Behind the Data Pattern<\/h3>\n

      The dose.dat<\/code> file reveals a characteristic pattern that validates this calculation method:<\/p>\n

        \n
      1. As the ion beam hits wafers with photoresist, outgassing begins and vacuum pressure rises immediately [2].<\/li>\n
      2. Simultaneously, measured beam current decreases due to charge-exchange neutralization reactions (ions capture electrons from gas molecules) [1][3].<\/li>\n
      3. When implantation continues beyond peak outgassing, the effect gradually diminishes as resist desorption slows down.<\/li>\n<\/ol>\n\n

        Verification<\/h2>\n

        After calculating PCOMP using this method:<\/p>\n

          \n
        • Compare your calculated pressure-compensated beam current (Iactual<\/sub> or pcompI<\/code>) against expected values [2].<\/li>\n
        • Verify that compensated current shows minimal standard deviation during implant (ideally constant throughout) rather than varying with end station pressure fluctuations [3].<\/li>\n<\/ul>\n\n

          Recommended Resources for Further Study<\/h2>\n

          For more detailed information on Dose.dat analysis and PCOMP determination, refer to these Axcelis documentation sources:<\/p>\n

            \n
          • Best Methods and Practices for Determining Pressure Compensation Factors Using Dose_dat Software<\/em> (Part Number 9510721) [1]<\/li>\n
          • Dose Theory and Pressure Compensation on Axcelis GSD High Current Implanter<\/em> \u2013 Published paper by Infineon Technologies AG, IEEE Proceedings [3]<\/li>\n<\/ul>\n\n

            References<\/h2>\n
              \n
            1. Axcelis Dose_dat Training Documentation, File ID: 150d0f20-2e1e-440d-8506-e684b7f7355d<\/li>\n
            2. most detail for IMPL training.pdf \u2013 Axcelis Process Lab Documentation, File ID: 21a3f7ab-a105-4906-8372-3660bd997da7<\/li>\n
            3. Kraupner J., Kyek A., Vogl J., Weiss S. “Dose Theory and Pressure Compensation on Axcelis GSD High Current Implanter” \u2013 IEEE Proceedings, 2002<\/li>\n<\/ol>\n\n

              Summary for Students<\/h2>\n

              When explaining this to your students, emphasize these key teaching points:<\/p>\n

                \n
              • PCOMP is necessary because photoresist outgassing causes variable pressure, which creates neutralization reactions that distort dose uniformity.<\/li>\n
              • The disk faraday cup measures electric charge (current), but not the actual particle flux of dopants reaching the wafer surface.<\/li>\n
              • Dose.dat analysis provides a data-driven, non-destructive method to validate or optimize PCOMP without splitting production lots for experimental measurements.<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"

                Overview The dose.dat fil […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[89],"tags":[],"class_list":["post-3646","post","type-post","status-publish","format-standard","hentry","category-live"],"_links":{"self":[{"href":"https:\/\/blog.zengqq.com.cn\/index.php?rest_route=\/wp\/v2\/posts\/3646","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.zengqq.com.cn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.zengqq.com.cn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.zengqq.com.cn\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.zengqq.com.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3646"}],"version-history":[{"count":1,"href":"https:\/\/blog.zengqq.com.cn\/index.php?rest_route=\/wp\/v2\/posts\/3646\/revisions"}],"predecessor-version":[{"id":3647,"href":"https:\/\/blog.zengqq.com.cn\/index.php?rest_route=\/wp\/v2\/posts\/3646\/revisions\/3647"}],"wp:attachment":[{"href":"https:\/\/blog.zengqq.com.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3646"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.zengqq.com.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3646"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.zengqq.com.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3646"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}