The invention discloses a preparation method for an epitaxial
diode array isolated by double shallow trenches. The method includes the following steps: a heavily doped first
conductivity type region and a highly doped second
conductivity type region are first formed on a substrate, an epitaxial layer is grown, the isolation between work lines of the
diode array is then formed by
deep trench etching, the isolation between bit lines, which is perpendicular to the
deep trench direction, is formed by shallow trench
etching, and finally, independent
diode array units are formed in regions defined by the
deep trench isolation and the
shallow trench isolation by the method of
ion injection. The invention also provides an inhibition method for the
crosstalk current between the neighboring word lines and bit lines, which is based on the epitaxial
diode array isolated by the double shallow trenches. The invention is applicable to high-density, high-capacity memories driven by diodes, such as
phase change memories, resistive memories, magnetic memories and ferroelectric memories; the method is fully compatible with the conventional
CMOS (Complementary
Metal-
Oxide-
Semiconductor Transistor) technique, the
diode array is formed before a
peripheral circuit is formed, so that the thermal process of the
diode array cannot cause the drift of the
peripheral circuit, and the invention solves the technical problem on how to achieve a high-density, high-capacity embedded
phase change memory.