Invented by Chang Sung Sean Kim, Jong Pa HONG, Joong El Ghim, Samsung Electronics Co Ltd
The Samsung Electronics Co Ltd invention works as followsThe invention provides a chemical vapor-deposition apparatus that includes a reaction room, a susceptor mounted in the chamber, and a rotating unit for rotating the susceptor. It also provides a gas intake in the chamber that introduces reaction gases from outside the chamber, a gas discharge in the chamber that discharges the finished reaction gas from inside the chamber in the direction of rotation of the susceptor, and a variable-flow-adjustment unit between the gas inlet, and gas outlet.
Background for Chemical vapor deposition apparatus
The present invention is a chemical vapor evaporation apparatus that includes a variable-flow adjusting device which distributes the reaction gas uniformly into a reaction room.
In general, CVD is used to grow various crystal films on different substrates.
The growth rate of crystals is low compared to LPE.
To overcome this problem, it is common to use a method of growth in which multiple substrates are grown simultaneously in one cycle.
However when films are grown simultaneously on multiple substrates, it is important to maintain the temperature and reaction gas flow of each substrate in order for the films on those substrates to be the same quality.
To achieve this construction, different methods were used. In the first method, gas is constantly maintained on the substrates by using several injection pipes. In a secondary method, several substrates can be arranged in a circular shape around a rotation axis. They are then rotated along the same axis. In a third technique, multiple substrates can be rotated independently of each other. These methods can be used separately or in combination.
The uniform flow of reaction gas can’t be achieved in the case of a method where several substrates are arranged along one rotation axis. Reaction gas is introduced from outside the reaction chamber into the interior of the chamber, perpendicularly to the rotation axis. It is therefore difficult to grow high-quality thin films on a wafer.
The present invention has the advantage that it includes a gas-flow-adjusting unit that uniformly distributes the reaction gas introduced into an reaction chamber. This results in a thin film of high quality.
The description will include additional aspects and benefits of the general inventive idea. Some of these will be evident from the description or can be learned through the practice of this general inventive idea.
According to one aspect of the invention a chemical vapour deposition apparatus includes a reaction room; a susceptor mounted in the chamber with a plurality wafers; a rotating unit that rotates susceptor, a gas intake that is located in the chamber that introduces gas from outside the chamber into the chamber; and a gas discharge that is situated in the chamber that discharges the finished reaction gas from inside the chamber in the direction of rotation of susceptor.
The chemical vapor deposition device may also include a heating unit located on one side of the susceptor to radiate heat onto the susceptor.
The gas jetting plate unit is preferably superimposed from the outside the reaction chamber towards the center.
The gas jetting plates that make up the variable gas flow adjusting unit can be shaped in a ring.
The variable gas-flow adjustment unit can adjust the reaction gas flow based on the area of overlap between the holes that occur when a gas jetting plate or a plurality of gas jetting plates is rotated.
The holes in the gas jetting plates that make up the variable gas flow adjusting unit can be inclined in an eccentric direction with respect to the center of rotation for the susceptor.
The inclination of the holes in the gas jetting plates can be changed to change the direction of the gas reaction jetted by the variable gas-flow adjustment unit.
The direction eccentric to the center of rotation of the susceptor can be reversed to the direction of rotation of the susceptor.
The holes in the gas jetting plates that make up the variable gas flow adjusting unit can be circular, elliptical or polygonal shaped.
The holes in the gas jetting plates that make up the variable gas flow adjusting unit can have a slit-shaped opening which extends either in a vertical or horizontal direction.
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