Nitride semiconductor thin film having fewer defects and method of growing the same

The present invention relates to a nitride semiconductor thin film having less defects and a method of growing the same. According to the present invention, the nitride semiconductor thin film with lower defect density can be manufactured by forming grooves on a substrate, sequentially forming a buffer layer and a first nitride semiconductor thin film on a whole surface of the substrate, etching higher defect density regions of the first nitride semiconductor thin film, and then laterally growing a second nitride semiconductor thin film. Thus, a highly crystalline nitride semiconductor thin film can be obtained. Therefore, there are advantages in that high-efficiency, high-power and high-reliability optical devices or electronic devices can be manufactured and high throughput can also be obtained by using the obtained nitride semiconductor thin film.