The invention relates to a structure for improving the
breakdown voltage of a vertical type
diamond MOSFET through a High K
dielectric and a preparation method thereof.The structure comprises
a diamond substrate, an epitaxial layer, a groove,
a diamond regeneration layer, a source
electrode, a
passivation layer, a gate
electrode, a High K
dielectric layer and a drain
electrode, the High K
dielectric layer is introduced to the surface of the groove, the
electric flux distribution is guided through the high dielectric constant characteristic of the High K
dielectric layer, and therefore the
breakdown voltage of the vertical type
diamond MOSFET is improved. Therefore, the
electric field distribution of the channel region is optimized, an
electric field regulation and
control effect similar to a super junction is formed, and the source-drain
breakdown voltage of the vertical
diamond MOSFET is effectively improved without damaging the on-resistance. The preparation method comprises the steps of substrate selection, epitaxial growth,
dry etching to form a groove, regeneration layer repair, formation of a source electrode and a drain electrode, surface terminal treatment,
passivation layer deposition, gate electrode deposition, introduction of a High K
dielectric layer and the like. By introducing the High K dielectric on the surface of the diamond channel, high breakdown
voltage and low on-resistance are taken into account, and the high-
power semiconductor device is suitable for the field of high-power electronic devices.