Exposure apparatus, mask plate and exposing method
An exposure apparatus comprises: a loading stage for supporting a substrate; a mask plate parallel to the loading stage and above the loading stage, the mask plate including a light transmitting region and a light absorbing region on its lower surface, a light reflecting region being provided in the light absorbing region; a lens device provided between the mask plate and the loading stage; a first illumination light source, light from which vertically striking on the upper surface of the mask plate from above, passing through the mask plate and striking on the loading stage via the lens device; a light reflecting device provided in the lens device; and a second illumination light source, light from which being reflected onto the lower surface of the mask plate by the light reflecting device located in the lens device, the light being reflected by the light reflecting region on the lower surface of the mask plate and striking on the loading stage via the lens device.
1. An exposure apparatus, comprising:
a loading stage for supporting a substrate;
a mask plate parallel to the loading stage and provided above the loading stage, the mask plate including a light transmitting region, a light absorbing region, a light reflecting region provided in the light absorbing region on a lower surface of the mask plate;
a lens device provided between the mask plate and the loading stage;
a first illumination light source, light from which vertically strikes on the upper surface of the mask plate from above, passes through the mask plate and strikes on the loading stage via the lens device;
a light reflecting device provided in the lens device; and
a second illumination light source, light from which is reflected onto the lower surface of the mask plate by the light reflecting device located in the lens device, then is reflected by the light reflecting region on the lower surface of the mask plate and strikes on the loading stage via the lens device.
2. The exposure apparatus according to claim 1 , wherein the lens device comprises an isosceles trapezoid lens, and a upper base plane and a lower base plane of the isosceles trapezoid lens are vertical to the mask plate; and
the light reflecting device comprises a reflecting mirror provided.
3. The exposure apparatus according to claim 2 , wherein if an angle between an upper waist plane and the lower base plane of the isosceles trapezoid lens is “b,”
the refractive index of the upper waist plane of the isosceles trapezoid lens is “n,”
an angle between the light reflected upward by the reflecting mirror and the normal of the upper waist plane of the isosceles trapezoid lens is “c,” then c=arc sin(cos b/n) is satisfied;
an intersection angle of the reflecting mirror and the horizontal level is “a,” and 2a=b+c.
4. The exposure apparatus according to claim 2 , wherein light emitted by from second illumination light source is vertically reflected onto the lower surface of the mask plate via the lens device.