SOLID IMMERSION LENS, AND SAMPLE OBSERVING METHOD USING IT

摘要

The image of a sample (2) is observed by using a solid immersion lens (SIL) (1) formed of a material having a refractive index nL so as to have a spherical lens plane (10) having a radius of curvature RL. During the sample observation, geometric aberration characteristics by the SIL (1) are evaluated using a specified optical system. With a coefficient k (0<k<1) so set as to satisfy a condition under which its average image plane is flat and a condition under which good chromatic aberration characteristics are available, a plane containing a point located k x (RL/nL) downstream the spherical center (C) of the lens plane (10) along the optical axis (Ax) and being orthogonal to the optical axis (Ax) is used as a sample observing plane (20) to observe a sample using the SIL (1). Accordingly, a sample observing method able to observe the good image of a sample using a solid immersion lens, and a solid immersion lens are realized.