| 摘要 |
<P>PROBLEM TO BE SOLVED: To increase the fineness of a wiring pattern without reducing the mechanical strength of a tent membrane in a method for exposing a blank for a printed wiring board. <P>SOLUTION: A blank 30 for a printed wiring board is prepared by sequentially stacking a substrate layer 21, a metal layer 23 and a photosensitive layer 19 having sensitivity to light of a predetermined wavelength, wherein the photosensitive layer 19 is formed by sequentially stacking from the metal layer 23 side a high sensitivity photosensitive layer 13 having high sensitivity to light of the predetermined wavelength and a low sensitivity photosensitive layer 12 having lower sensitivity to light of the predetermined wavelength than the high sensitivity photosensitive layer 13 and having a larger thickness than the high sensitivity photosensitive layer 13. The blank 30 is irradiated with laser light Le having the above predetermined wavelength from the photosensitive layer 19 side while condensing the laser light Le on a position P in the high sensitivity photosensitive layer 13, whereby the photosensitive layer 19 is exposed and cured. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
