The invention discloses a measuring method and device for focusing and leveling, and relates to a new method for the focusing and leveling
sensor system of a
wafer applicable to the projection
photolithography system, and belongs to the field of optical measurement. The invention consists of three parts, namely, a
light source collimating module, a focusing subsystem and a leveling subsystem. The
laser of the invention emits
laser light, the
laser light is collimated by a single mode
fiber and then passes through a drift compensation device, and then permeates a polarized optical splitter and a
Lambda fourth wave plate and then shines on a measured
silicon chip. The
ray is led to pass through the measured
silicon chip repeatedly through a planar mirror and a corner cube
prism, and then is magnified in front of a
position detector by a lens
system, thereby obtaining the defocusing information of the
silicon chip surface. The
ray is rebounded along the path by a planar optical splitter, the
ray permeates a lens and shines on a position-sensitive
detector, thereby obtaining the two-dimensional inclination information of the
silicon chip surface. The
system has
high resolution as well as simple structure of
optical path and needs no complicated optical design.