Patent Publication Number: US-2012031336-A1

Title: Chemical vapor deposition device

Description:
BACKGROUND 
     1. Technical Field 
     The disclosure relates to chemical vapor deposition devices, and more particularly to a chemical vapor deposition device for printing optical films. 
     2. Description of the Related Art 
     A number of microstructures are formed on a deposition roll of a chemical vapor deposition device. However, because particles can contaminate the surface of the microstructures, the thickness of films formed by chemical solution deposition is not uniform. 
     Therefore, it is desired to provide a new chemical vapor deposition device which can overcome the above-mentioned limitations. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Many aspects of the embodiments can be better understood with references to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the embodiments. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views. 
         FIG. 1  is schematic view of a chemical vapor deposition device in accordance with one embodiment of the disclosure. 
         FIG. 2  is a cross-section taken along line II-II of the chemical vapor deposition device in  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
     The disclosure is illustrated by way of example and not by way of limitation in the figures of the accompanying drawings. It should be noted that references to “an” or “one” embodiment in this disclosure are not necessarily to the same embodiment, and such references mean at least one. 
     Referring to  FIGS. 1-2 , a chemical vapor deposition device  100  in accordance with one embodiment of the disclosure includes a chamber  10 , a gas input assembly  20 , a gas output assembly  30 , a heating device  40 , a driving module  50  and an ionization device  60 . 
     The chamber  10  includes a first side  11 , a second side  12  and a deposition area  13 . The second side  12  is opposite to the first side  11 . The deposition area  13  is defined between the first side  11  and the second side  12 . In use, a deposition roll  70  is located in the deposition area  13 . In the embodiment, a sidewall of the chamber  10  corresponding to the deposition area  13  is curved. 
     The gas input assembly  20  is configured for inputting reaction gases to the deposition roll  70  in the chamber  10  to form a film on a surface of the deposition roll  70 . The gas output assembly  30  is configured for exhausting the gases in the chamber  10  for generating a stable airflow. 
     The heating device  40  is configured for heating the deposition area  13  in the chamber  10  to maintain a stable temperature around the surface of the deposition roll  70 . Thus, the reaction gas around the surface of the deposition roll  70  can be heated to obtain a proper reaction temperature. 
     The driving module  50  is configured for driving the deposition roll  70  to rotate relative to a rotating shaft  71  of the deposition roll. Thus, uniform film can be formed on the surface of the deposition roll  70 . The ionization device  60  is configured for ionizing the reaction gases in the chamber  10  to concentrate the ions of the gases around the surface of the deposition roll  70 . The efficiency of forming films on the surface of the deposition roll  70  increases accordingly. 
     The chemical vapor deposition device  100  further includes two bearings  15 . The two bearings  15  are configured for supporting the shaft  71  of the deposition roll  70 . A line defined between the two bearings  15  is perpendicular to a line defined between a center of the first side  11  and a center of the second side  12 . The two bearings  15  can be rolling bearings or sliding bearings. 
     The gas input assembly  20  is positioned on an upper portion of the first side  11 . The gas input assembly  20  includes a jet module  21 . The jet module  21  is configured for injecting air to the deposition area  13 . The gas input assembly  20  is connected to a gas source (not shown). In the embodiment, the gas input assembly  20  is defined on the center of the upper side of the first side  11 . 
     The reaction gases can be different gases, such as (SiH 4 , N 2 ), (AlCl 3 , NH 3 ) or (TiCl 4 , N 2 , H 2 ). The reaction gases can be changed to obtain films of different characters. The different reaction gases can be mixed in advance or respectively introduced to the deposition area  13 . 
     Optimally, the jet module  21  includes a plurality of nozzles (not shown). The mixed gas can be mixed more uniformly through the nozzles. The different gases can also be respectively introduced to the surface of the deposition roll  70  through the plurality of the nozzles and then be mixed uniformly. Optimally, the directions of the nozzles can be adjusted. Therefore, the gas can be introduced to different areas of the surface of the deposition roll  70  through the nozzles from different directions. 
     The gas output assembly  30  is positioned on a bottom portion of the second side  12  of the chamber  10 . The gas output assembly  30  is configured for exhausting reaction air from the chamber  10 . Air flow from the first side  11  to the second side  12  will be generated through the gas output assembly  30 . Accordingly, the airflow from the first side  11  to the second side  12  goes through the deposition area  13 . 
     The airflow through the deposition area  13  increases the distribution area of the air and exhausts the gas that has not reacted. 
     The chemical vapor deposition device  100  further includes a tube  17 . The tube  17  is defined in the second side  12  of the chamber  10 . The gas output assembly  30  includes a gate  31  and a pump  33 . The tube  17  passes through the sidewall of the second side  12 . The gate  31  is defined in the tube  17  and is adjacent to the exterior of the chamber  10 . The gate  31  is configured for adjusting the exhausted gas flowing through the tube  17 . 
     The heating device  40  is defined in the bottom of the deposition area  13  and defined on the sidewall corresponding to the deposition area  13 . The heating device  40  is configured for heating the deposition area  13  and providing proper reaction temperature for the reaction gases. In the embodiment, the heating device  40  includes a plurality of heating windings  41 . The heating windings  41  are resistive and regularly defined below the chamber  10  corresponding to the deposition area  13 . Thus, the heating device  40  can uniformly heat the deposition area  13 . 
     The driving module  50  is connected to the deposition roll  70  in the deposition area  13 . The driving module  50  is configured for driving the deposition roll  70  from the first side  11  to the second side  12 . The deposition roll  70  rotates relative to the rotating shaft  71 . 
     The driving module  50  can be defined in the chamber  10  and adjacent to the gas output assembly  30 . The driving module  50  can also be defined outside of the chamber  10 . The driving module  50  includes a motor  51  and a belt  53 . The motor  51  is connected to the shaft  71  through belt  53 . The driving module  50  can control the rotational velocity. Accordingly, the reaction gases on the surface of the deposition roll  70  can be substantially reacted. 
     The ionization device  60  is defined on upper side of the chamber  10 . The ionization device  60  faces the deposition area  13 . The ions of the gas generated by the ionization device  60  are distributed around the deposition area  13 . The ionization device  60  is configured for adjusting the density of the ions around the deposition area  13 . In the embodiment, the ionization device  60  is planar and parallel to the shaft  71  of the deposition roll  70 . A length of the ionization device  60  exceeds that of the deposition roll  70 . Thus, the ions of the reaction gas can be substantially distributed on the surface the deposition roll  70 . 
     In the deposition process, the film thickness on different surfaces of the deposition roll  70  can be adjusted through the nozzles of different directions, rotational velocity of the deposition roll  70  and the density of the ions of reaction gas. 
     The deposition areas on the surface of the deposition roll  70  can be adjusted through the nozzles of different directions. Thus, a large-sized deposition area can be obtained. Thickness of film formed on the plurality of micro-structures of the deposition roll  70  can be uniform. 
     While the disclosure has been described by way of example and in terms of exemplary embodiment, it is to be understood that the disclosure is not limited thereto. To the contrary, it is intended to cover various modifications and similar arrangements (as would be apparent to those skilled in the art). Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.