Abstract:
The present disclosure relates to a deposition apparatus used to manufacture a semiconductor device including a process chamber; a substrate susceptor installed in the process chamber and including a plurality of concentrically arranged stages on which substrates are positioned; a plurality of members for supplying reaction gas; a member for supplying purge gas; a spray member including a plurality of baffles for independently spraying reaction gas and purge gas, supplied from the plurality of members supplying reaction gas and the member supplying purge gas, on the entirety of the treating surfaces of the substrate, in positions corresponding respectively to the substrates positioned on the stages; and a driving unit for rotating the substrate susceptor or the spray member in order for the baffles of the spray member to sequentially revolve each of the plurality of substrates positioned on the stages.

Description:
TECHNICAL FIELD 
     The present invention disclosed herein relates to an apparatus used to manufacture a semiconductor device, and more particularly, to a susceptor supporting a substrate and an apparatus including the susceptor to perform a deposition process. 
     BACKGROUND ART 
     In a deposition process of processes for manufacturing a semiconductor device, an atomic layer deposition process is introducing to improve conformability of a deposited layer. The atomic layer deposition process is a process in which a unit reaction cycle for depositing a layer with a thickness similar to that of an atomic layer is repeated to form a deposition layer with a desired thickness. However, according to the atomic layer deposition process, it takes a long time to grow a layer having a desired thickness because a deposition rate is very slow when compared to a chemical vapor deposition process or a sputtering process. Thus, productivity may be decreased. 
     Furthermore, temperature uniformity of a susceptor on which a substrate is placed is one of the biggest factors, which have an influence on uniformity with respect to a thickness of a thin film to be deposited on the substrate. The susceptor may thermally affect the substrate according to a disposition shape of a heating element to cause non-uniformity of the layer. Thus, the susceptor should have a thick thickness to reduce the influence of the heating element arrangement, thereby securing the temperature uniformity. 
     SUMMARY 
     Technical Problem 
     The present invention provides a substrate susceptor capable of improving thermal efficiency and a deposition apparatus having the same. 
     The present invention also provides a substrate susceptor capable of minimizing a loss of heat generated from a heating element without heating a substrate and a deposition apparatus having the same. 
     The present invention also provides a substrate susceptor capable of improving temperature uniformity and a deposition apparatus having the same. 
     The feature of the present invention is not limited to the aforesaid, but other features not described herein will be clearly understood by those skilled in the art from descriptions below. 
     Technical Solution 
     In order to solve the aforementioned problems, embodiments of the present invention provide deposition apparatuses including: a process chamber; a substrate susceptor in which a plurality of substrates are placed on the same plane, the substrate susceptor being disposed in the process chamber; and a spray member disposed at a position corresponding to that of each of the plurality of substrates placed on the substrate susceptor to spray a gas onto an entire processing surface of the substrates, wherein the substrate susceptor includes: an upper susceptor including stages on which the substrates are placed on a top surface thereof; a lower susceptor coupled to a bottom surface of the upper susceptor, the lower susceptor including a heating element for heating the substrate disposed on an area corresponding to each of the stages; and a barrier member disposed on a bottom surface of the lower susceptor to prevent heat energy from being radiated into the bottom of the lower susceptor. 
     In some embodiments, the substrate susceptor may have a radiant space for transferring heat between the lower susceptor and the barrier member. 
     In other embodiments, the barrier member may include a plate-shaped barrier plate on which a reflective coating layer is disposed on a top surface thereof contacting the radiant space, wherein the barrier plate may be disposed corresponding to the stages. 
     In still other embodiments, the barrier plate may have a curved top surface or an inclined top surface. 
     In even other embodiments, the barrier plate may include patterns having an intaglio or relievo roughness on the top surface thereof to concentrate a radiant angle of heat energy into a specific area. 
     In yet other embodiments, the substrate susceptor may include a pore for transferring a heating source of the heating element between the upper susceptor and the lower susceptor, which are disposed under the states, in a radiative transfer manner. 
     In further embodiments, the pore is filled with a silicon carbide-based material in which a carbon nano tube having high heat capacity and low heat conductivity is mixed. 
     In order to achieve the above problems, a substrate susceptor comprising: an upper susceptor comprising a plurality of stages on which substrates are placed on a concentric circle thereof; a lower susceptor coupled to a bottom surface of the upper susceptor, the lower susceptor comprising a heating element for heating the substrate; and a barrier plate disposed corresponding to each of the stages on a bottom surface of the lower susceptor, to resupply heat energy radiated from the lower susceptor toward the upper susceptor, thereby improving heat efficiency. 
     In some embodiments, the substrate susceptor may include: a first pore uniformly transferring the heat energy of the heating element between the upper susceptor and the lower susceptor, which are disposed under the stages; and a second pore transferring the heat energy reflected from the barrier plate between the lower susceptor and the barrier plate. 
     In other embodiments, the barrier plate may have a reflective coating layer is disposed on a top surface thereof contacting the second pore, and the barrier plate may include patterns having an intaglio or relievo roughness on the top surface of the barrier plate thereof to concentrate a radiant angle of heat energy into a specific area. 
     Advantageous Effects 
     According to the present invention, the substrate placed on the susceptor may be minimized in temperature distribution deviation. 
     Also, according to the present invention, the thermal efficiency during the heating may be improved. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a view of an atomic layer deposition apparatus according to the present invention. 
         FIGS. 2 and 3  are perspective and cross-sectional views of a spray member shown in  FIG. 1 . 
         FIG. 4  is a perspective view of a substrate susceptor shown in  FIG. 1 . 
         FIG. 5  is a cross-sectional view of a main part of the substrate susceptor. 
         FIGS. 6 to 9  are views illustrating various modified examples of a barrier member. 
         FIG. 10  is a view of a barrier member according to another embodiment of the present invention. 
         FIG. 11  is a view illustrating a modified example of the barrier member shown in  FIG. 10 . 
         FIG. 12  is a view of a barrier member according to another embodiment of the present invention. 
         FIG. 13  is a view of a barrier member according to another embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Preferred embodiments of the present invention will be described below in more detail with reference to the accompanying drawings. The objective, technical solution, and merits of the present invention may be easily understood through the accompanying drawings and related embodiments. In the drawings, the dimensions of layers and regions are exaggerated for clarity of illustration. It is noted that like reference numerals denotes like elements in appreciating the drawings. Moreover, detailed descriptions related to well-known functions or configurations will be ruled out in order not to unnecessarily obscure subject matters of the present invention. 
     Embodiments 
       FIG. 1  is a view of an atomic layer deposition apparatus according to the present invention.  FIG. 2  is an exploded perspective view of a spray member of  FIG. 1 .  FIG. 3  is a cross-sectional view of the spray member of  FIG. 1 .  FIG. 4  is a perspective view of a substrate susceptor shown in  FIG. 1 . 
     Referring to  FIGS. 1 to 4 , an atomic layer deposition apparatus  10  includes a process chamber  100 , a substrate susceptor  200  that is a substrate support member, a spray member  300 , and a supply member  400 . 
     The process chamber  100  has an entrance  112  in a side thereof. Substrates W may be loaded or unloaded into/from the process chamber  100  through the entrance  112  during the processing. Also, the process chamber  100  includes an exhaust duct  120  and an exhaust tube  114  which exhaust a reaction gas and purge gas, which are supplied therein, and byproducts generated during an atomic layer deposition process at an upper edge thereof. The exhaust duct  120  is disposed outside the spray member  300  and has a ring shape. Although not shown, a vacuum pump, and a pressure control valve, a switching valve, and a flow control valve may be installed in the exhaust tube  114 . 
     Referring to  FIGS. 1 to 3 , the spray member  300  sprays a gas onto each of four substrates placed on the substrate susceptor  200 . The spray member  300  receives first and second reaction gases and a purge gas from the supply member  400 . The spray member  400  is configured to spray the gases supplied from the supply member  400  onto an entire processing surface of each of the substrates at positions corresponding to those of the substrates. The spray member  300  includes a head  310  and a shaft  330 . The head  310  includes first to fourth baffles  320   a  to  320   d , respectively. The shaft  330  is disposed on an upper center of the process chamber  100  to support the head  310 . The head  310  has a disk shape. Also, the first and fourth baffles  320   a  to  320   d  have independent spaces for receiving the gases into the head  310 , respectively. The first to fourth baffles  320   a  to  320   d  have fan shapes which are successively partitioned by an angle of about 90 degrees with respect to a center of the head  310 , respectively. Gas discharge holes  312  are defined in bottom surfaces of the first to fourth baffles  320   a  to  320   d , respectively. The gases supplied from the supply member  400  are supplied into the independent spaces of the first to fourth baffles  320   a  to  320   d , respectively. The gases are sprayed through the gas discharge holes  312  and then provided onto the substrate. A portion of the baffles  320   a  to  320   d  may supply a different kind of gas. Portions of the baffles  320   a  to  320   d  may have supply the same gas. For example, a first reaction gas is supplied into the first baffle  320   a , and a second reaction gas is supplied into the third baffle  320   c  facing the first baffle  320   a . Also, the purge gas for preventing the first and second reaction gases from being mixed with each other and for purging a non-reaction gas is supplied into the second and fourth baffles  320   b  and  320   d.    
     For example, the head  310  may have a fan shape in which the first to fourth baffles  320   a  to  320   d  are successively arranged at about 90 degrees. However, the present invention is not limited thereto. For example, four baffles or less or more may be provided according to purposes and characteristics of the process. For example, eight baffles may be successively arranged at about 45 degrees. Alternatively, two baffles may be arranged at about 180 degrees. Also, the whole or a portion of the baffles may have sizes different from each other. 
     Referring again to  FIG. 1 , the supply member  400  includes a first gas supply member  410   a , a second gas supply member  410   b , and a purge gas supply member  420 . The first gas supply member  410   a  supplies the first reaction gas for forming a predetermined thin film on a substrate W into the first baffle  320   a . The second gas supply member  410   b  supplies the second reaction gas into the third baffle  320   c . The purge gas supply member  420  supplies the purge gas into the second and fourth baffles  320   b  and  320   d . Here, the purge gas supply member  420  continuously supplies the purge gas at a uniform flow rate. However, the first and second gas supply members  410   a  and  410   b  discharge (a flash supply manner) the reaction gas charged at a high pressure using a high pressure charging tank (not shown) for a short time to diffuse the reaction gas on the substrate. 
     Although two gas supply members are provided to supply two reaction gases different from each other in the current embodiment, the present invention is not limited thereto. For example, a plurality of gas supply members may be applied to supply at least three reaction gases different from each other according to the process characteristics. 
     Referring to  FIGS. 1 and 4 , the substrate susceptor  200  is installed in an inner space of the process chamber  100 . The substrate susceptor  200  may be a batch type in which four substrates are placed. The substrate susceptor  200  is rotated by a driving unit  290 . A stepping motor including an encoder which is capable of controlling a rotation rate and speed of a driving motor may be used as the driving unit  290  rotating the substrate susceptor  200 . A process time of one cycle (first reaction gas—purge gas—second reaction gas—purge gas) of the spray member  300  may be controlled by the encoder. 
     The substrate susceptor  200  may have three stages, but four stages, or four stages or more. 
     Although not shown, the substrate susceptor  200  may include a plurality of lift pins (not shown) for lifting the substrate W on each stage. The lift pins lifts the substrate W to space the substrate W from the stage of the substrate susceptor  200  or seat the substrate W on the stage. 
     The substrate susceptor  200  includes an upper susceptor  210 , a lower susceptor  220 , a heating element  230 , a barrier member  240 , and a support pillar  280  supporting the lower susceptor  220 . 
     The upper susceptor  210  is coupled to the lower susceptor  220  to overlap with each other in a disk shape on which first to fourth stages  212   a  to  212   d  on which the substrates are mounted are disposed. Each of the first to fourth stages  212   a  to  212   d  disposed on the upper susceptor  210  may have a circular shape similar to that of the substrate W. The first to fourth stages  212   a  to  212   d  may be successively disposed on a concentric circle at an angular distance of about 90 degrees with respect to the center of the substrate susceptor  200 . 
     The lower susceptor  220  includes the heating element  230  for heating the substrate W seated on each of the stages  212   a  to  212   d  of the upper stage  210  on a top surface thereof. A heating wire may be used as the heating element  230 . The heating element  230  is disposed in an insertion groove  228  defined in the top surface of the lower susceptor  220  in a state where the heating element  230  is supported by a holder  232 . The holder  232  may be disposed on the whole heating element  230 . Alternatively, the holders are successively disposed with a predetermined length or a predetermined angle (for example, about 90 degrees or 45 degrees) to fix the respective heating elements  230 . The heating element  230  heats the upper susceptor  210  and the lower susceptor  220  to increase a temperature of the substrate W to a preset temperature (a process temperature). The heating wire of the heating element  230  may be disposed in different manners on a stage area (the heating wire is densely disposed) on which the substrate W is placed and an area (the heating wire is dispersedly disposed) except the stage area to increase a temperature of the stage area on which the substrate W is placed and decrease a temperature of the area except the stage area, thereby depositing the thin film only on the substrate W. 
       FIG. 5  is a cross-sectional view of a main part of the substrate susceptor. Referring to  FIG. 5 , a first pore  250  having a diameter of several mm is defined between the upper susceptor  210  and the lower susceptor  220 . Also, a second pore  260  having a diameter of several mm is defined between the lower susceptor  220  and the barrier member  240 . 
     The first pore  250  is defined between the upper susceptor  210  and the lower susceptor  220  under the state. Heat energy of the heating element  230  may be transferred into the upper susceptor  210  in a radiative transfer method, not a conductive method and therefore temperature uniformity of the upper susceptor  210  is improved. As another example, although not shown, a heat transfer sheet formed of a silicon carbide-based material having high heat capacity and low heat conductivity may be disposed in the first pore  250  to improve a heat transfer rate. The heat transfer sheet has a single or multi layer structure in which a carbon nano tube for transferring heat into silicon carbide in one direction is mixed. The carbon nano tube may be adjusted in mixture ratio for each area (a central portion and an edge portion) of the heat transfer sheet to control a heat transfer ratio for each area of the heat transfer sheet. 
     Referring again to  FIG. 5 , the barrier member  240  may prevent a portion of the heat energy generated in the heating element  230  disposed on the top surface of the lower susceptor  220  from being radiated into a bottom surface of the lower susceptor  220 , thereby preventing a loss of the heat energy. The barrier member  240  is disposed on the bottom surface of the lower susceptor  220 . The second pore  260  that is a radiant space for transferring heat is defined between the barrier member  240  and the lower susceptor  220 . 
     The barrier members  240  are arranged with an angle of about 90 degree on a concentric circle with respect to a center of the substrate susceptor  200  and disposed on the bottom surface of the lower susceptor  220  corresponding to the respective stages, like the stages. The barrier member  240  includes a barrier plate  241 , having a circular plate shape, on which a reflective coating layer  244  is coated so that the heat energy radiated into the bottom surface of the lower susceptor  220  is resupplied toward the lower susceptor  220  to improve thermal efficiency. The barrier plate  241  is formed of a material having a low heat capacity such as quartz. Also, a thin film  244  (a reflective coating layer) formed of platinum or molybdenum, which is thermally and chemically stable, is coated on a surface of the barrier plate  241  to improve reflective efficiency. 
     The barrier plate  241  may have various shapes except the flat plate shape as shown in  FIG. 4 . 
       FIGS. 6 to 9  are views illustrating various modified examples of a barrier member. 
     Referring to  FIGS. 6 and 7 , a barrier plate  241  of barrier member  240   a  or  240   b  may have a concave or convex shape. That is, in the case where the barrier plate  241  has the concave shape recessed from an edge portion toward a central portion, a retro-reflective angle of the radiant energy may be concentrated into the central portion. On the other hand, in the case where the barrier plate  241  has the convex shape protruding form an edge portion toward a central portion, the retro-reflective angle of the radiant energy may be concentrated into the edge portion. That is, the barrier plate  241  may have variously changed in shape so that the reflective angle of the radiant energy is concentrated into a specific area to further increase a temperature of the specific area. 
     Referring to  FIG. 8 , patterns having a roughness may be disposed on a top surface of the barrier plate  241  of a barrier member  240   c . The patterns may improve the retro-reflective efficiency of the radiant energy radiated from the bottom surface of the lower susceptor  220  and adjust the retro-reflective angle. Also, the barrier member  240   c  may further increase a temperature of the specific area by using the patterns to improve reflectance. The patterns may include intaglio patterns or relievo patterns. Alternatively, each of the patterns may have various shapes such as a dotted shape, a polygonal shape, a V shape, and a cone shape. 
     The barrier member  240   d  shown in  FIG. 9  may be configured to concentrate the reflective angle of the radiant energy into the specific area by forming the patterns having shapes different from each other on the central and edge portions of the top surface of the barrier plate  241 . 
       FIG. 10  is a view of a barrier member according to another embodiment of the present invention. In  FIG. 10 , a barrier member  240   e  is disposed on a top surface of a lower susceptor  220 . In this case, the barrier member  240   e  retro-reflects radiant energy radiated from a bottom surface of an upper susceptor  210  and lower radiant energy of a heating element. Here, the heating element  230  may be disposed at a position higher than that of a top surface of the lower susceptor  220  to improve reflective efficiency, thereby further exposing the heating element  230  to a first pore. When the heating element  230  is exposed to the top surface of the lower susceptor  220 , the radiant energy emitted from the heating element  230  toward the top surface of the lower susceptor  220  may be reflected in a direction of the upper susceptor  210  to improve thermal efficiency. 
       FIG. 11  is a view illustrating a modified example of the barrier member shown in  FIG. 10 . A heating element  230  is directly disposed on a top surface of a barrier member  240   f  and thus is disposed on a top surface of the lower susceptor. Also, the heating element  230  is fixed to the top surface of the barrier member  240   f  by holders  232 . Also, the holders  232  may be disposed with a predetermined distance or at a predetermined angle. 
       FIGS. 12 and 13  are views of a barrier member according to another embodiment of the present invention. 
     Referring to  FIGS. 12 and 13 , each of barrier members  240   g  and  240   h  includes a barrier plate  241 , having a circular plate shape, on which a reflective coating layer  244  is coated and a case  249  sealing the barrier plate  241  and having a second pore  260  that is a radiant space for transferring heat. The case  249  is formed of transparent quartz. The case  249  may prevent a process gas (a reaction gas) from being permeated, thereby preventing reflectance from being deteriorated due to the contamination of a barrier plate  241  and a reflective coating layer  244 , an abnormal reaction, and impurities. 
     As shown in  FIG. 8 , the barrier member  240   g  may be disposed on a top surface of a lower susceptor  220 . In this case, a heating element  230  is disposed on a top surface of a case  249  of the barrier member  240   g.    
     Also, as shown in  FIG. 13 , the barrier member  240   h  may be disposed on a bottom surface of the lower susceptor  220 . Since the barrier member  240   h  has a radiant space for transferring heat in itself, the barrier member  240   h  may be closely attached to the lower susceptor  220  without providing a separate space between the barrier member  240   h  and the lower susceptor  220 . 
     The above-disclosed subject matter is to be considered illustrative, and not restrictive, and the appended claims are intended to cover all such modifications, enhancements, and other embodiments, which fall within the true spirit and scope of the present invention. Thus, to the maximum extent allowed by law, the scope of the present invention is to be determined by the broadest permissible interpretation of the following claims and their equivalents, and shall not be restricted or limited by the foregoing detailed description.