Light emitting device and manufacturing method thereof

A method for manufacturing a light emitting device comprising the steps of:

• forming a thin film transistor over a substrate;
• forming an insulating layer over the thin film transistor;
• forming a film over the insulating layer;
• forming a contact hole through the insulating layer and the film;
• forming a first electrode over the film, the first electrode being electrically connected to the thin film transistor through the contact hole;
• forming a second electrode being electrically connected to the first electrode;
• removing a part of the film by using the second electrode as a mask;
• forming a bank over the second electrode so as to cover an edge of the film and the second electrode;
• forming a light emitting layer over the second electrode;
• and
• forming a third electrode over the light emitting layer.

A method for manufacturing a light emitting device comprising the steps of:

• forming a thin film transistor over a substrate;
• forming an insulating layer over the thin film transistor;
• forming a film over the insulating layer;
• forming a contact hole through the insulating layer and the film;
• forming a first electrode over the film, the first electrode being electrically connected to the thin film transistor through the contact hole;
• removing a part of the film by using the first electrode as a mask;
• forming a bank over the first electrode so as to cover an edge of the film and the first electrode;
• performing a heat treatment to the insulating layer;
• forming a light emitting layer over the first electrode;
• and
• forming a second electrode over the light emitting layer.

A method for manufacturing a light emitting device comprising the steps of:

• forming a thin film transistor over a substrate;
• forming an insulating layer over the thin film transistor;
• forming a film over the insulating layer;
• forming a contact hole through the insulating layer and the film;
• forming a first electrode over the film, the first electrode being electrically connected to the thin film transistor through the contact hole;
• forming a second electrode being electrically connected to the first electrode;
• removing a part of the film by using the second electrode as a mask;
• forming a bank over the second electrode so as to cover an edge of the film and the second electrode;
• performing a heat treatment to the insulating layer;
• forming a light emitting layer over the second electrode;
• and
• forming a third electrode over the light emitting layer.