Method of manufacturing printed circuit board

A method of manufacturing a printed circuit board, the method comprising:

• forming a resist layer;
• exposing first areas of the resist layer spaced apart from each other;
• after exposing the first areas, exposing second areas of the resist layer, the second areas being spaces between the first areas;
• forming first and second openings spaced apart from each other in the first and second areas by developing the resist layer;
• and
• forming a plurality of conductor patterns by filling the first and second openings with conductors,
• wherein the first openings include a 1-1st opening and a 1-2nd opening spaced apart from each other,
• the second openings include a 2-1st opening and a 2-2nd opening spaced apart from each other,
• the plurality of conductor patterns include a 1-1st conductor pattern formed in the 1-1st opening, a 1-2nd conductor pattern formed in the 1-2nd opening, a 2-1st conductor pattern formed in the 2-1st opening, and a 2-2nd conductor pattern formed in the 2-2nd opening,
• when the plurality of conductor patterns are taken in cross sections thereof in a thickness direction, each of WP1-1, WP1-2, WP2-1, and WP2-2 is 0.5 μm or more and 5 μm less, where WP1-1 is an average line width of the 1-1st conductor pattern, WP2-1 is an average line width of the 2-1st conductor pattern, WP1-2 is an average line width of the 1-2nd conductor pattern, and WP2-2 is an average line width of the 2-2nd conductor pattern, and
• a ratio of a width of each of spaces between the 1-1st, 2-1st, 1-2nd, and 2-2nd conductor patterns with respect to an average height of the 1-1st, 2-1st, 1-2nd, and 2-2nd conductor patterns is more than ¼ and less than ⅗.