Film forming apparatus

A film forming apparatus comprising:

• a processing chamber including an inner tube and an outer tube surrounding the inner tube, wherein the inner tube includes a gas exhaust port for exhausting gas in the inner tube;
• a first gas supply pipe coupled to a first gas source for supplying a first type of gas and a second gas supply pipe coupled to a second gas source, which is separated from the first gas source, for supplying a second type of gas that is different from the first type of gas, wherein each of the first gas supply pipe and the second gas supply extends vertically in the processing chamber and including a plurality of gas holes, including a plurality of first gas holes and a single second gas hole, each of the plurality of gas holes of the first gas supply pipe has a same opening size, wherein all of the plurality of first gas holes of the first gas supply pipe are arranged in two columns extending along the first gas supply pipe, each first gas hole of one column of the first gas supply pipe and a corresponding first gas hole of the other column of the first gas supply pipe are at an equal height, all of the first gas holes of the second gas supply pipe being arranged in two columns extending along the second gas supply pipe, each first gas hole of one column of the second gas supply pipe and a corresponding first gas hole of the other column of the second gas supply pipe are at an equal height;
• and
• a boat configured to accommodate a plurality of substrates including product substrates in a vertical direction in the processing chamber, wherein a height of the gas exhaust port is identical to or greater than a total height of the boat,
• wherein the film forming apparatus forms a film on each of the plurality of substrates by use of gas supplied from the plurality of gas holes, each of the plurality of substrates corresponding to respective one or more of the plurality of gas holes, and
• wherein gas holes among the plurality of gas holes that are arranged in a height range in which the product substrates are situated include the first gas holes that are opened at a same height, the first gas holes being oriented at respective angles such that respective imaginary lines passing through the first gas holes and a central axis of the first gas supply pipe are at a same angle relative to a first imaginary line passing through the central axis of the first gas supply pipe and a center of a corresponding one of the product substrates, and respective imaginary lines passing through the first gas holes and a central axis of the second gas supply pipe are at an identical angle relative to a second imaginary line passing through the central axis of the second gas supply pipe and the center of the corresponding one of the product substrates,
• wherein the first gas supply pipe includes a plurality of the first gas holes at a first height and a plurality of the first gas holes at a second height greater than the first height, an angular separation between two of the first gas holes about the central axis of the first gas supply pipe at the first height being different from an angular separation between two of the first gas holes about the central axis of the first gas supply pipe at the second height,
• wherein the second gas supply pipe includes a plurality of the first gas holes at a third height that is identical to the first height and a plurality of the first gas holes at a fourth height greater than the third height, an angular separation between two of the first gas holes about the central axis of the second gas supply pipe at the third height being different from an angular separation between two of the first gas holes about the central axis of the second gas supply pipe at the fourth height,
• wherein the film forming apparatus further comprises at least one valve configured to switch between the first gas supply pipe and the second gas supply pipe to supply gas into the processing chamber, so as to adjust an inplane distribution of the film formed on the product substrates,
• wherein an angular separation between two of the first gas holes of the first gas supply pipe about the central axis of the first gas supply pipe at the first height is different from an angular separation between two of the first gas holes of the second gas supply pipe about the central axis of the second gas supply pipe at the third height,
• wherein an angle between a gas discharge direction of each of the first gas holes of the first gas supply pipe at the first height and the first imaginary line is greater than 0 degree and less than or equal to 90 degrees,
• wherein an angle between a gas discharge direction of each of the first gas holes of the second gas supply pipe at the third height and the second imaginary line is greater than 0 degree and less than or equal to 90 degrees, and
• wherein the plurality of gas holes, arranged in the height range in which the plurality of product substrates are situated, includes the single second gas hole positioned at a top of the first gas supply pipe, the single second gas hole being opened in a same direction as the first imaginary line.