| 摘要 |
PURPOSE: To improve performance by determining the contrast versus thickness characteristics of a photoresist, optimizing the contrast of the photoresist, and selecting the resist thickness. CONSTITUTION: The contrast of photo-resist layer 18 determines the nonlinear relationship of the photoresist contrast for the thickness of the photoresist. The contrast of the phtoresist can be optimized by applying the photoresist 18 with a thickness, that corresponds to a desired contrast value being indicated by the nonlinear relationship between the thickness of the photoresist and the contrast over a substrate 20. The nonlinear contrast function for the thickness of the photoresist is expressed by an attenuated sinusoidal wave curve, difference between the maximum and minimum contrast values of the function decreases as the resist thickness increases, and the absolute maximum value of contrast further increases as the resist thickness decreases. By selecting the optimum resist thickness, a high-density product can be obtained without using a contrast reinforcing material that is expensive and has many defects. |
