| 摘要 |
<p>PURPOSE:To make resist pattern opaque, after it is formed on the glass substrate, by leaving it in the atmosphere of Freon gas, so that a photo mask can be obtained which is cheaper in cost and facilitate minute working. CONSTITUTION:Photo resist pattern 2 is formed on one surface of the glass substrate 1 by the ultraviolet ray exposure process, electron beam exposure process or X-ray exposure process. The substrate is left standing for a certain period of time in Freon gas plasma which has a gas pressure of 0.5 Torr and an RF power of 20 W. The light transmissivity of pattern 2 with respect to wave length, by using the abovementioned standing time of the photo mask as a parameter, is shown in the figure on the right. From this figure, it is observed that if standing time is made longer, the photo mask will become opaque against ultraviolet rays for exposure of less than 400 mm. The reason for the photo mask to become opaque is not clear, but it may considered that the organic polymer in the resist reacts with the Freon gas. In this way, a mask can be made which is cheaper in cost and easily allows minute working.</p> |
