Inkjet printing device, method for aligning bipolar element, and method for manufacturing display device

A method for aligning a bipolar element, comprising:

• spraying ink including a bipolar element oriented in an extension direction onto a target substrate, the bipolar element comprising a semiconductor;
• and
• generating an electric field above the target substrate to place the bipolar element on the target substrate wherein
• the electric field is generated using electrodes disposed above the target substrate and spaced apart from the target substrate, and
• the electric field affects an orientation of the bipolar element.

A method for manufacturing a display device, comprising:

• preparing a target substrate on which a first electrode and a second electrode are formed;
• spraying ink including a light emitting element oriented in a direction onto the target substrate, wherein the light emitting element has a shape extending in an extension direction, and wherein the spraying of the ink comprises generating an electric field in a nozzle such that a long axis of the light emitting element is oriented in a direction that the electric field faces;
• and
• placing the light emitting element between the first electrode and the second electrode.