This paper presents a new rewritable capacitance disk memory with a fe
rroelectric-semiconductor structure. The ferroelectric film of the med
ium was poled in the perpendicular direction to generate depletion cap
acitance for data recording. Capacitance between the stylus head and t
he medium was detected for data reproduction. The amount of change in
capacitance due to the poling direction showed that the recording dens
ity of this memory system could be more than 1 Gbit/cm(2). Evaluation
equipment was constructed for dynamic bit recording and reproduction,
in which the mobile stylus head was in contact with the medium surface
. It was confirmed that data bits with 0.4 mu m spatial wavelength cou
ld be recorded and reproduced. In our experiment, recording density wa
s mostly determined by the stylus size, and its limit was also estimat
ed by the numerical simulation of ferroelectric semiconductor structur
e.