Apparatus for the photolithographic manufacture of integrated circuit elements

An apparatus for the photolithographic printing of a pattern onto a semiconductor substrate, comprising:

• a substantially horizontal support for said semiconductor substrate;
• means for horizontally moving said support in mutually orthogonal X and Y directions for step-by-step exposure of successive portions of said semiconductor substrate;
• a projection lens disposed above said support and said semiconductor substrate for imaging a pattern of a mask upon each of the successive portions of said semiconductor substrate to activate a photosensitive layer thereon, as said portions are aligned with said lens by the movement of said support in said X and Y directions;
• a basin carried by and movable with said support, receiving said semiconductor substrate and having an upper rim lying above at least a lower face of said lens whereby said lower face projects into said basin;
• and
• flexible pipe mens for feeding a transparent liquid having a refractive index close to that of said layer into said basin, for removing said liquid from said basin and for maintaining the level of liquid in said basin always above said lower face for imaging of said pattern upon said successive portions under constant conditions of filling of the space between said layer and said face with said liquid, said liquid being capable of wetting said layer and substantially incapable of attacking same.