Preparation method of gallium nitride amplitude limiter and gallium nitride amplitude limiter

The invention provides a preparation method of a gallium nitride amplitude limiter and the gallium nitride amplitude limiter. The method comprises the following steps: etching at a first preset position after epitaxial growth of an N-GaN layer to obtain a PIN diode mesa; etching is carried out at a second preset position of the exposed area on the N-GaN layer, and a Schottky diode mesa is obtained on the N + GaN layer; etching at a third preset position of the exposed area on the N + GaN layer to perform mesa isolation; preparing ohmic contact on the exposed region of the N + GaN layer; electrodes are manufactured in the exposed areas on the N + GaN layer and the P + GaN layer and the exposed areas on the N + GaN layer and the N-GaN layer, and the gallium nitride amplitude limiter is obtained. The gallium nitride amplitude limiter can be rapidly obtained in an etching mode, pollution is little, and the prepared gallium nitride amplitude limiter is large in power capacity, high in breakdown voltage and good in