| 摘要 |
PURPOSE:To enable the evaluation of inner-face uniformity with high reliability, by a method wherein a concentration profile is examined after first ion implantation and, based on the result of the examination, second ion implantation is executed for preparing a field effect transistor, when a field effect transistor for evaluation is prepared. CONSTITUTION:An active layer 4 is formed by implantation of Si into a semi- insulating GaAs substrate 5. After the first implantation annealing, an area of a liquid level Schottky 2 by tiron is made to be of a prescribed value by means of a rubber-like ring 3, the measurement of capacity-voltage based on Schottky-Schottky is conducted by using a capacitance bridge 1, and thereby a concentration profile can be found. Since the static characteristic of a field effect transistor can be supposed by calculation when said profile is found, second ion implantation is executed for compensating the profile. Thereby the value of the profile is made to approximate a theoretical curve 6 as indicated by a curve 8 in the figure. Thus, the measurement of the inner-face uniformity of a wafer conducted after the characteristic of the field effect transistor is modified by this method gains higher reliability than prior art measurements. |
