Micro-fluidic chip, library preparation chip and method for controlling and driving droplet

A micro-fluidic chip, comprising:

• a first base substrate;
• a first electrode on the first base substrate and electrically coupled to a wire at a driving end;
• a second electrode on a side of the first electrode away from the first base substrate and spaced apart and electrically insulated from the first electrode, the second electrode comprising a plurality of sub-blocks of the second electrode, and an orthographic projection of the second electrode on the first base substrate being at least partially overlapped with an orthographic projection of the first electrode on the first base substrate;
• and
• voltage-dividing resistors electrically coupled in parallel with each other, wherein each of the voltage-dividing resistors is coupled between a corresponding one of the plurality of sub-blocks of the second electrode and a ground wire,
• wherein the micro-fluidic chip further comprises a dielectric layer on a side of the second electrode away from the first base substrate and a second lyophobic layer on a side of the dielectric layer away from the first base substrate and the second lyophobic layer is configured to support a droplet and is in direct contact with the droplet,
• wherein resistance values of the voltage-dividing resistors gradually increase in a first direction, and voltages between the plurality of sub-blocks of the second electrode and the ground wire gradually increase in the first direction in proportion to the resistance values of the voltage-dividing resistors, and
• wherein each of the voltage-dividing resistors is formed by a conductive line having a square-wave shape, and lengths of the conductive lines forming the voltage-dividing resistors are different from one another and gradually increase in the first direction.