Array substrate, preparation method thereof, and display panel

A method for preparing an array substrate, comprising:

• forming a first thin film transistor and a second thin film transistor on a base substrate;
• wherein:
• said forming the first thin film transistor comprises:
• forming a pattern of a first gate electrode, a pattern of a first active layer, a pattern of a first source electrode, and a pattern of a first drain electrode on the base substrate;
• said forming the second thin film transistor comprises:
• forming a pattern of a second gate electrode, a pattern of a second active layer, a pattern of a second source electrode, and a pattern of a second drain electrode on the base substrate;
• wherein:
• a material of the first active layer is different from a material of the second active layer;
• and
• said forming the pattern of the first active layer comprises:
• forming a guide structure;
• forming a pattern of at least one catalyst particle on at least one side of the guide structure, the catalyst particle and silicon having a eutectic point;
• forming an amorphous silicon film covering the catalyst particle and the guide structure;
• annealing the amorphous silicon film so that amorphous silicon grows from the catalyst particle in an extending direction of the guide structure to form a silicon-based nanowire;
• and
• removing the catalyst particle and retaining the amorphous silicon film and the silicon-based nanowire in a first preset area to form the pattern of the first active layer, the catalyst particle being outside the first preset area.