Vapor deposition apparatus
A vapor deposition apparatus of the present invention has a substrate holder having a substrate holding surface for holding a substrate thereon, and a flow channel for supplying a source gas onto the substrate. The flow channel has an upper wall and a lower wall. An aperture portion is provided in the lower wall of the flow channel. The substrate holding surface of the substrate holder fits in the aperture portion while forming a space between the substrate holding surface and the aperture portion. A means for reducing leakage of gas through the space between the aperture portion and the substrate holder is provided. With this structure, since a means for reducing leakage of gas through the space between the aperture portion and the substrate holder is provided, the conductance with respect to outflow of gas increases, which in turn reduces variations in the amount of outflow gas. This results in high yield production of nitride semiconductor devices with a long life and high light-emission efficiency.
1 . A vapor deposition apparatus comprising:
a substrate holder comprising a substrate holding surface for holding a substrate thereon;
a flow channel for supplying a source gas onto the substrate, the flow channel comprising an upper wall and a lower wall;
an aperture portion provided in the lower wall of the flow channel, the substrate holding surface of the substrate holder fitting in the aperture portion while forming a space between the substrate holding surface and the aperture portion; and
a means for reducing leakage of gas through the space between the aperture portion and the substrate holder.
2 . The vapor deposition apparatus according to claim 1 , wherein the means for reducing leakage of gas is formed by bending the space from an inside of the flow channel to an outside thereof.
3 . The vapor deposition apparatus according to claim 1 , wherein the means for reducing leakage of gas comprises:
an upward dent portion dented in an upward direction, the upward dent portion being provided along a periphery of the aperture portion and in a thickness portion of the lower wall of the flow channel; and
a brim projecting from a side wall of the substrate holder in a lateral direction, the brim fitting in the upward dent portion while forming a space between the brim and the upward dent portion, when the substrate holding surface of the substrate holder is in a state of fitting in the aperture portion.
4 . The vapor deposition apparatus according to claim 3 , wherein the space formed between the aperture portion of the flow channel and the substrate holder comprises a bent passage, the bend passage comprising a first passage extending downward from an inside of the flow channel, a second passage extending in a lateral direction from an end of the first passage, and a third passage extending from an end of the second passage down to an outside of the flow channel.
5 . The vapor deposition apparatus according to claim 1 , wherein the means for reducing leakage of gas comprises a brim projecting from a side wall of the substrate holder in a lateral direction, while forming a space between the brim and the lower wall of the flow channel, when the substrate holding surface of the substrate holder is in a state of fitting in the aperture portion.
6 . The vapor deposition apparatus according to claim 5 , wherein the space formed between the aperture portion of the flow channel and the substrate holder comprises a bent passage, the bend passage comprising a first passage extending downward from an inside of the flow channel, and a second passage extending in a lateral direction from an end of the first passage to an outside of the flow channel.
7 . The vapor deposition apparatus according to claim 1 , further comprising a mechanism for revolving the substrate holder.
8 . The vapor deposition apparatus according to claim 1 , further comprising:
a heater for heating the substrate, the substrate holder holding the substrate being mounted on the heater, the heater being vertically movable and provided below the aperture portion of the flow channel;
a mounting mechanism for mounting the substrate holder on the heater; and
a moving mechanism for moving the heater with the substrate holder mounted thereon while fitting the substrate holding surface of the substrate holder in the aperture portion of the flow channel.
9 . The vapor deposition apparatus according to claim 1 , the substrate holder comprises a disk comprising a brim provided along its side wall.
10 . The vapor deposition apparatus according to claim 1 , wherein the vapor deposition apparatus is used as an MOCVD apparatus for vapor deposition of a nitride semiconductor.