  We have produced thick-foil and fine-pitch gas electron multipliers (GEMs)
using a laser etching technique. To improve production yield we have employed a
new material, Liquid Crystal Polymer, instead of polyimide as an insulator
layer. The effective gain of the thick-foil GEM with a hole pitch of 140 um, a
hole diameter of 70 um, and a thickness of 100 um reached a value of 10^4 at an
applied voltage of 720 V. The measured effective gain of the thick-foil and
fine-pitch GEM (80 um pitch, 40 um diameter, and 100 um thick) was similar to
that of the thick-foil GEM. The gain stability was measured for the thick-foil
and fine-pitch GEM, showing no significant increase or decrease as a function
of elapsed time from applying the high voltage. The gain stability over 3 h of
operation was about 0.5%. Gain mapping across the GEM showed a good uniformity
with a standard deviation of about 4%. The distribution of hole diameters
across the GEM was homogeneous with a standard deviation of about 3%. There was
no clear correlation between the gain and hole diameter maps.
