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测定离子注入后掺杂总数的方法可分为二大类。一类是对注入层进行直接分析;另一类是借助于对物理性能和器件参数的测量而间接地测定其掺杂数量。对这些方法作了简要的评述后,报导了对离子注入的剂量精度和均匀性的一次国际性的调研结果:它是用直径为76mm的硅片,注入硼离子,并在一组规范的条件下进行了退火,用四探针法对被调研的注入后的每一块硅片上的118个点进行了薄层电阻值的自动测量。调研中的85台离子注入机所测的方块电阻的总平均值为169.7Ω/□,相对它的标准偏差为8.1Ω/□,这表明了工业用离子注入机存在的定标范围。等值薄层电阻轮廊图曾用于鉴别均匀性问题,它提供了一个易于解积的图示方法。在一个硅片内薄层电阻值的非均匀性(一个标准偏差)变化范围是0.37％到4.76％,其中值为0.72％。
The method of determining the total amount of doping after ion implantation can be divided into two broad categories. One is to directly analyze the injection layer; the other is to indirectly determine the amount of doping by means of the measurement of physical properties and device parameters. After a brief review of these methods, an international survey of dose accuracy and uniformity of ion implantation was reported: using a 76 mm diameter silicon wafer, boron ions were implanted, and under a set of canonical conditions Annealed, and four-probe method was used to measure the sheet resistance of 118 points on each silicon wafer under investigation. The average of the sheet resistance measured by the 85 ion implanters in the survey was 169.7Ω / □ with a relative standard deviation of 8.1Ω / □, indicating the calibration range available for industrial ion implanters. Equivalent thin-layer resistance turbo maps were used to identify homogeneity problems, providing an easy-to-deconsolidate graphical approach. The inhomogeneity (one standard deviation) of sheet resistance within a silicon wafer varies from 0.37% to 4.76% with a value of 0.72%.