1. Field of the Invention
The present invention relates to a film, a manufacturing method thereof, and a substrate structure including the film. More specifically, the present invention relates to a manufacturing method of a nitride crystalline film, a nitride film, and a substrate structure including the nitride film.
2. Description of Related Art
With the development of electronic technology, the thin film deposition technique has been widely used in the manufacture of electronic devices. The thin film deposition is mainly categorized into two groups, physical vapor deposition (PVD) and chemical vapor deposition (CVD), where the former is mainly applied in deposition of metal materials, and the application scope of the latter includes deposition of dielectric materials, conductive materials, and semiconductor materials. The technique of semiconductor thin film deposition can be utilized in the manufacture of light emitting diode (LED). Moreover, the quality of semiconductor thin film deposition directly affects the optoelectronic property, the reliability, and the lifetime of an LED chip.
FIG. 1 is a schematic view of a conventional LED chip. Referring to FIG. 1, sequentially from bottom to top, the conventional LED chip 100 includes a sapphire substrate 110, a buffer layer 120, an undoped gallium nitride epitaxial layer 130, an N-type gallium nitride epitaxial layer 140, a light emitting layer 150, and a P-type gallium nitride epitaxial layer 160. In addition, a positive electrode 172 is disposed on the P-type gallium nitride epitaxial layer 160, and a negative electrode 170 is disposed on the N-type gallium nitride epitaxial layer 140. Since the lattice constants of the gallium nitride lattice and the sapphire lattice do not match, in order for the N-type gallium nitride epitaxial layer 140 to obtain a stable lattice structure, the buffer layer 120 is formed on the sapphire substrate 110. Thus, the undoped gallium nitride epitaxial layer 130 formed on the buffer layer 120 then forms a stable lattice structure, and the N-type gallium nitride epitaxial layer 140 formed on the undoped gallium nitride epitaxial layer 130 also obtains a stable lattice structure.
The conventional LED chip 100 is also used to produce a thin LED (vertical type) chip, of which the manufacturing method includes first removing the sapphire substrate 110. In the conventional LED chip 100, the buffer layer 120 and the undoped gallium nitride epitaxial layer 130 are still present between the N-type gallium nitride epitaxial layer 140 and the sapphire substrate 110. Therefore, the buffer layer 120 and the undoped gallium nitride epitaxial layer 130 still need to be removed sequentially after the removal of the sapphire substrate 110. Thereby, the manufacturing steps of the thin LED (vertical type) chip increase, thus resulting in long manufacturing time and difficulty in reducing manufacturing costs.