Thin-film deposition device and deposition method

Abstract

To provide a thin-film deposition device and a thin-film deposition method that can improve the performance of a product by securing high directivity of a vapor-phase material or material particles emitted from a material source during a thin-film deposition process, converting a point source or line source in a device into a plane source with respect to various deposition techniques such as vacuum heat vapor deposition and molecular beam epitaxy, eliminating an influence of a shadow, and improving deposition uniformity.SOLUTION: A thin-film deposition device includes: a plurality of vaporization sources 20 arranged in a lower region of a wall 10 of a film coating chamber of the thin-film deposition device; corresponding curved surface reflectors 30 arranged at positions of the respective vaporization sources; a plane reflector 40 arranged in the lower region of the wall of the film coating chamber; and a beam splitter 50 arranged in an intermediate region of the wall of the film coating chamber, in which the beam splitter includes a plurality of beam splitter components, the plane reflector is further arranged in the horizontal direction of the beam splitter, and heating components 13 are arranged at the plane reflector, curved surface reflector, and beam splitter components.SELECTED DRAWING: Figure 1A

Description

[Technical field]

[0001] The present invention relates to the field of semiconductor product manufacturing, and more particularly to thin film deposition apparatus and methods. [Background technology]

[0002] In deposition techniques such as vacuum thermal evaporation and molecular beam epitaxy, in order to improve the uniformity and refine the structure of the fabricated materials and devices, it is necessary to increase the requirements for the direction of the gas phase material and material particles emitted from the material source (such as the evaporation source) during the thin film deposition process. Currently, the material sources used in vacuum thin film deposition techniques such as vacuum thermal evaporation and molecular beam epitaxy are mostly point sources or line sources. The material beams emitted from these material sources often have different angles of incidence with respect to the normal of the substrate, which results in shadow effects and non-uniformity of thin film deposition. In vacuum deposition techniques such as vacuum thermal evaporation and molecular beam epitaxy, a gas phase material beam (such as an atomic beam, ion beam, molecular beam, or other form of material beam) is emitted from a point source or line source in an approximately straight line and flies inside the vacuum cavity. When the vapor material beam encounters the cavity wall base, condensation wall, mask plate, substrate, or other device surface, adsorption, secondary evaporation, or reflection occurs. The angle of incidence is defined as the angle between the velocity direction of the atomic beam, molecular beam, or material particle when it hits the substrate and the normal to the substrate. The angle of incidence is usually 0-90°. The smaller the angle of incidence, the better the quality and uniformity of the thin film deposition, and the smaller the effective size of the microstructure of the thin film device microstructure. In view of this, the surface source technology has attracted certain attention and has been extensively studied. Surface source refers to a film coating source with a planar structure. Compared with point or line sources, the atomic beam, molecular beam, or material particle, etc. emitted from the surface source can be perpendicularly incident on the substrate, so its angle of incidence is 0°. At present, the method based on the surface source in the field of vacuum thermal evaporation generally involves first depositing the materials of the point source or line source together on a low-temperature intermediate substrate, and then heating the intermediate substrate toward the final substrate, so that the entire material film on the intermediate substrate is deposited on the final substrate. These surface source technologies involve many difficulties, are inefficient and costly, so it is difficult to popularize them in a short period of time.

[0003] In the prior art entitled "Thin Film Deposition Apparatus and Thin Film Deposition Method" (Patent Document 1), the thin film deposition apparatus of the prior art includes a thin film deposition chamber, the thin film deposition chamber includes a cavity housing surrounding the cavity of the thin film deposition chamber, a target bracket disposed in the center of the cavity and used to store a target made of component A, a substrate platform disposed in the center of the cavity and arranged to face the target bracket, a laser outlet disposed on a side of the cavity housing at an incline opposite to the target bracket for irradiating the target on the target bracket with a laser to generate a plasma plume, and a beam source furnace interface disposed on a side of the cavity housing at an incline opposite to the substrate platform for injecting a molecular beam stream made of component B. The laser outlet and the beam source furnace interface inject the laser and the molecular beam stream simultaneously. The present invention effectively avoids mutual interference between the film formation process by pulsed laser deposition and the film formation process by molecular beam epitaxy, and can produce a better quality thin film than the prior art can produce.

[0004] However, this technology is not related to the technical problem and technical solution of the present invention. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] China Patent Application Publication No. 103103480 Summary of the Invention [Problem to be solved by the invention]

[0006] The technical problem to be solved by the present invention is to provide a thin film deposition apparatus which is simple in structure, low in cost, convenient and reliable to use, ensures high directionality of gas phase material or material particles emitted from a material source during the thin film deposition process, converts a point source or line source in the apparatus into a surface source in various deposition techniques such as vacuum thermal evaporation and molecular beam epitaxy, eliminates the shadow effect, improves the uniformity of thin film deposition, and ultimately improves product performance. [Means for solving the problem]

[0007] In order to solve the above technical problems, the technical solutions of the present disclosure are as follows:

[0008] According to a first aspect of the present invention, there is provided a thin film deposition apparatus including a wall of a film coating chamber, in which a plurality of evaporation sources are disposed in a lower region of the wall of the film coating chamber, a curved reflector is disposed corresponding to the position of each evaporation source, a flat reflector is further disposed in the lower region of the wall of the film coating chamber, and a beam splitter is disposed in an intermediate region of the wall of the film coating chamber, the beam splitter includes a plurality of beam splitter components, each beam splitter is disposed at an acute angle with respect to the horizontal direction, a flat reflector is further disposed horizontally of the beam splitter, the flat reflector is disposed at an acute angle with respect to the horizontal direction, and a heating component is disposed on each of the flat reflector, the curved reflector and the beam splitter component.

[0009] The substrate and a mask plate are arranged from top to bottom in the upper region of the wall of the film-coating chamber, the substrate being a silicon wafer, and the diameter of the mask plate being larger than that of the substrate.

[0010] The beam splitter components of the beam splitter are arranged from top to bottom, and two adjacent beam splitter components are arranged in an acute angle configuration.

[0011] Each of the evaporation sources includes a nozzle, and each of the evaporation sources' nozzles is directed toward one of the curved reflectors, and each of the curved reflectors corresponds to one of the planar reflectors.

[0012] A flat reflector corresponding to each curved reflector is parallel to a corresponding beam splitter component, and each beam splitter component of the beam splitter has a rectangular prism structure, and an angle of each beam splitter component with respect to the horizontal direction is less than 30°.

[0013] The heating element is a resistance wire.

[0014] The curved reflector and flat reflector surfaces are surfaces of single crystal silicon 100, the surface roughness is less than 0.5 nm, the flat reflector is rectangular in shape, the curved reflector is a slotted paraboloid in shape, and the beam splitter includes a plurality of rectangular prism-shaped beam splitter components arranged.

[0015] The thin film deposition apparatus further includes a molecular beam epitaxy film coating apparatus, which includes a molecular beam emission slit, a liquid nitrogen cooled shield, and a source furnace flange.

[0016] According to another aspect of the present invention, the present invention further provides a thin film deposition method, which has simple steps, low cost, is convenient and reliable to use, ensures high directionality of gas phase material or material particles emitted from a material source during a thin film deposition process, and can convert a point source or line source in an apparatus into a surface source in various deposition techniques such as vacuum thermal evaporation and molecular beam epitaxy, eliminate shadow effects, improve the uniformity of thin film deposition, and ultimately improve product performance. The thin film deposition method includes steps S1, S2, S3, S4, and S5, In step S1, each evaporation source emits a material beam from a nozzle, each material beam is emitted toward a corresponding curved reflector, and each material beam is reflected by a corresponding flat reflector, and each flat reflector ejects the corresponding material beam onto the surface of a corresponding beam splitter part of the beam splitter, and all the material beams are coated or doped on the substrate after passing through the top beam splitter part; In step S2, when the vertically propagating material beam is injected onto the surface of the corresponding beam splitter part of the beam splitter, a part (about half) of the material beam is horizontally reflected onto the base of the wall of the film coating chamber, and a part (about the remaining half) of the material beam continues to propagate after being vertically reflected; In step S3, when a horizontally propagating material beam is injected onto a surface of a corresponding beam splitter part of the beam splitter, all of the material beam is reflected and propagated vertically; In step S4, the vertically and horizontally propagating material beams are reflected by the beam splitter to form a mixed vertical material beam, which is incident on the top beam splitter component; In step S5, the material beams emitted from different evaporation sources are irradiated onto the substrate at the same small angle after passing through the top beam splitter component, and the deposition is completed after coating or doping. Effect of the Invention

[0017] The technical solution of the present invention has the following working principles and beneficial effects:

[0018] According to the thin film deposition apparatus and deposition method of the present invention, the apparatus of the present invention includes a number of reflectors, beam splitters and other components, and can uniformly mix and shape the material beams emitted from one or more gas phase material point or line sources into a surface source. The apparatus can be used to manufacture thin films or epitaxy devices with high uniformity and low shadow effect, improving the quality of the thin film and reducing the effective size of the device microstructure. During the deposition process, each evaporation source 20 emits a material beam 70 from a nozzle 21, each material beam is emitted toward a corresponding curved reflector 30, each material beam 70 is reflected by a corresponding flat reflector, each flat reflector 40 ejects the corresponding material beam 70 onto the surface of the corresponding beam splitter component 52 of the beam splitter, and all the material beams 70 are coated or doped on the substrate 11 after passing through the top beam splitter component. When a vertically propagating material beam is injected onto the surface of the corresponding beam splitter part 52 of the beam splitter 50, a portion 70 (about half) of the material beam is horizontally reflected to the base of the wall of the film coating chamber, and a portion 70 (about the remaining half) of the material beam continues to propagate after being vertically reflected. When a horizontally propagating material beam is injected onto the surface of the corresponding beam splitter part of the beam splitter, all of the material beam is reflected to propagate vertically. The vertically and horizontally propagating material beams are reflected by the beam splitter to become a mixed vertical material beam, which is incident on the top beam splitter part. The material beams emitted from different evaporation sources are coated or doped on the substrate at the same small angle after passing through the top beam splitter part, and the deposition is completed after coating or doping. [Brief description of the drawings]

[0019] The contents shown in the drawings accompanying this specification and the reference numerals therein will be briefly described below.

[0020] [Figure 1A] 1 is a schematic side view of the thin film deposition apparatus according to the present invention. [Figure 1B]FIG. 2 is a schematic plan view of a thin film deposition apparatus where the evaporation source is a point source. [Figure 1C] FIG. 1 is a perspective schematic view of a thin film deposition apparatus when the evaporation source is a line source, viewed from a 45° downward angle. [Figure 1D] FIG. 2 is a schematic side view of a thin film deposition apparatus where the evaporation source is a molecular beam epitaxy deposition apparatus. [Figure 2A] FIG. 2 is a schematic diagram of the structure of a flat reflector. [Figure 2B] FIG. 2 is a schematic diagram of the structure of a curved reflector. [Figure 3A] FIG. 2 is a schematic side view of a beam splitter (point source beam splitter). [Figure 3B] FIG. 2 is a schematic plan view of a point source beam splitter. [Figure 4A] 1 is a diagram illustrating the principle by which a beam splitter reflects a material beam in the horizontal (lateral) direction. [Figure 4B] 1 is a diagram illustrating the principle by which a beam splitter reflects a material beam in the vertical direction (lengthwise). [Figure 4C] FIG. 1 illustrates the operating principle of a thin film deposition apparatus. [Diagram 5] 2A-2C are schematic diagrams of arbitrary cross-sectional shapes of the beam splitter part (reflector) of the beam splitter. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Specific embodiments of the present invention, such as the shapes and structures of various related components, the relative positions and connection relationships between the various components, the functions and operating principles of the various components, etc., will be described in further detail below through the description of the embodiments with reference to the accompanying drawings.

[0022] As shown in FIG. 1A-FIG. 5, the present invention provides a thin film deposition apparatus including a wall 10 of a film coating chamber. The wall 10 of the film coating chamber is divided into an upper region, a middle region, and a lower region. In the apparatus, a plurality of evaporation sources 20 are arranged in the lower region of the wall 10 of the film coating chamber, a corresponding curved reflector 30 is arranged at the position of each evaporation source 20, a flat reflector 40 is arranged in the lower region of the wall 10 of the film coating chamber, and a beam splitter 50 is arranged in the middle region of the wall 10 of the film coating chamber. The beam splitter 50 includes a plurality of beam splitter components 52. Each beam splitter component 52 is arranged at an acute angle with respect to the horizontal direction, and a flat reflector 40 is arranged horizontally of the beam splitter 50. The flat reflector 40 is arranged at an acute angle with respect to the horizontal direction. The heating component 13 is arranged on the flat reflector 40, the curved reflector 30, and the beam splitter component 52, respectively. The above structure provides an improved technical solution to address the deficiencies of the prior art. The entire deposition apparatus includes multiple reflectors, beam splitters and other components, which can uniformly mix and shape the material beams emitted from one or more gas-phase material point or line sources into a surface source. The apparatus can be used to manufacture thin films or epitaxy devices with high uniformity and low shadow effect, improving the quality of the thin film and reducing the effective size of the device microstructure. During the deposition process, each evaporation source 20 emits a material beam 70 through a nozzle 21, each material beam 70 is emitted to a corresponding curved reflector 30, each material beam 70 is reflected to a corresponding flat reflector 40, each flat reflector 40 ejects the corresponding material beam 70 onto the surface of the corresponding beam splitter component 52 of the beam splitter 50, and all the material beams 70 are coated or doped onto the substrate 11 after passing through the top beam splitter component 52. When a vertically propagating material beam 70 is injected onto the surface of a corresponding beam splitter component 52 of the beam splitter 50, a portion 70 (approximately half) of the material beam is reflected horizontally off the base of the film coating chamber wall, and a portion 70 (approximately the remaining half) of the material beam continues to propagate after being reflected vertically.When the horizontally propagating material beams 70 are injected onto the surface of the corresponding beam splitter parts 52 of the beam splitter 50, all of the material beams 70 are reflected and propagated vertically, and the vertically and horizontally propagating material beams 70 are reflected by the beam splitter 50 to become a mixed vertical material beam, which is incident on the top beam splitter part 52. The material beams 70 emitted from the different evaporation sources 20 are coated or doped on the substrate 11 at the same small angle after passing through the top beam splitter part 52, and the deposition is completed after coating or doping. The thin film deposition apparatus and the deposition method of the present invention are low in cost and convenient to use, and can ensure the high directionality of the gas phase material or material particles emitted from the material source during the thin film deposition process, and can convert the point source or line source in the apparatus into a surface source in various deposition techniques such as vacuum thermal evaporation and molecular beam epitaxy, eliminate the shadow effect, improve the uniformity of deposition, and improve the performance of the product.

[0023] In the upper region of the wall 10 of the film coating chamber, the substrate 11 and the mask plate 12 are arranged in the order from top to bottom, the substrate 11 is a silicon wafer, and the diameter of the mask plate 12 is larger than that of the substrate 11. In the above structure, when deposition is performed, the entire deposition operation is performed based on the wall 10 of the film coating chamber. The substrate and the mask plate are arranged at the upper part inside the wall 10 of the film coating chamber, and the material beam at the lower part is coated from top to bottom to complete the operation. When a deposition-ready thin film with a specific pattern structure needs to be deposited, the mask plate 12 with a specific pattern is arranged on the side of the substrate 11 for thin film deposition, and the deposition is not performed in the area of ​​the substrate 11 blocked by the mask plate 12, and the deposition is performed in the area hollowed out by the mask plate 12 to form the pattern. When the deposited thin film does not need to be patterned, the mask plate can be removed.

[0024] The beam splitter 50 has a plurality of beam splitter components 52 arranged from top to bottom, and two adjacent beam splitter components 52 have an acute angle structure. Each evaporation source 20 has a nozzle 21, and the nozzle 21 of each evaporation source 20 is directed to one curved reflector 30, and each curved reflector 30 corresponds to one flat reflector 40. One flat reflector 40 corresponding to each curved reflector 30 is parallel to one corresponding beam splitter component 52, and each beam splitter component 52 of the beam splitter 50 has a rectangular prism structure, and the angle of each beam splitter component 52 with respect to the horizontal direction is less than 30°. In the above structure, when the material in the material evaporation source is heated to the evaporation temperature, the material is continuously sprayed from the nozzle to the inner surface of the corresponding curved reflector at a certain speed in the form of gas or nanoparticles at various angles, and after being reflected by the parabolic surface of the curved reflector, the material beam becomes almost flat and is sprayed onto the surface of the flat reflector, and then deflected by the flat reflector and sprayed onto the surface of the beam splitter. Finally, the material beam 70 emitted from the different evaporation sources 20 is coated or doped onto the substrate 11 at the same small angle after passing through the top beam splitter part 52, and the deposition is completed after coating or doping.

[0025] The heating element 13 is a resistance wire. In the above structure, the heating wire is used for heating, so that the curved reflector, the flat reflector and the beam splitter are all high-temperature structures, which promotes the reflection of the material beam.

[0026] The surfaces of the curved reflector 30 and the flat reflector 40 are single crystal silicon (100) surfaces with a surface roughness of less than 0.5 nm, the flat reflector 40 is rectangular, the shape of the curved reflector 30 is a slotted paraboloid, and the beam splitter 50 is composed of an array of a plurality of rectangular prism-shaped beam splitter components 52. The thin film deposition apparatus further includes a molecular beam epitaxy film coating apparatus 60. The molecular beam epitaxy film coating apparatus 60 includes a molecular beam emission slit 61, a liquid nitrogen cooling shield 62, and a source furnace flange 63.

[0027] The present invention further provides a thin film deposition method, which has simple steps, low cost, convenient and reliable use, ensures high directionality of gas phase material or material particles emitted from a material source during the thin film deposition process, and can convert a point source or line source in the device into a surface source in various deposition techniques such as vacuum thermal evaporation and molecular beam epitaxy, eliminate the shadow effect, improve the uniformity of thin film deposition, and ultimately improve product performance. The deposition steps of the thin film deposition method include:

[0028] S1. Each evaporation source 20 emits a material beam 70 from a nozzle 21, each material beam 70 is emitted toward a corresponding curved reflector 30, each material beam 70 is reflected by a corresponding flat reflector 40, each flat reflector 40 ejects the corresponding material beam 70 onto the surface of a corresponding beam splitter component 52 of the beam splitter 50, and all the material beams 70 are coated or doped onto the substrate 11 after passing through the top beam splitter component 52.

[0029] S2. When the vertically propagating material beam 70 is injected onto the surface of the corresponding beam splitter component 52 of the beam splitter 50, a portion 70 (approximately half) of the material beam is reflected horizontally to the base of the wall of the film coating chamber, and a portion 70 (approximately the remaining half) of the material beam continues to propagate after being reflected vertically.

[0030] S3. When the horizontally propagating material beam 70 is projected onto the surface of the corresponding beam splitter component 52 of the beam splitter 50, all of the material beam 70 is reflected to propagate vertically.

[0031] S4. The vertically and horizontally propagating material beams 70 are reflected by the beam splitter 50 into a mixed vertical material beam that is incident on the top beam splitter component 52.

[0032] S5. The material beams 70 emitted from different evaporation sources 20 are coated or doped on the substrate 11 at the same small angle after passing through the top beam splitter component 52, and the deposition is completed after coating or doping.

[0033] The technical solutions and technical effects of the present invention to solve the technical problems are as follows:

[0034] The technical problems addressed by the present invention are as follows:

[0035] The material sources used in thin film vacuum deposition techniques such as vacuum thermal evaporation and molecular beam epitaxy are generally point or line sources. The incidence angle of the material beam emitted from these sources when deposited on the substrate is generally non-zero, and the incidence angle at different positions on the substrate is generally different, which reduces the uniformity of the deposited thin film. Thin film devices also have a large effective size of microstructures due to the shadow effect. In the above techniques, it is difficult to uniformly mix materials emitted from different material sources.

[0036] The technical solutions of the present invention to solve the technical problems are as follows:

[0037] An evaporation source with a heating component, a curved reflector, a flat reflector and a beam splitter are arranged. The material beams emitted from different point or line material sources are shaped into nearly parallel material beams by the curved reflector, and then redirected by the flat reflector before being emitted into a series of beam splitters arranged vertically, mixed with the material beams emitted from the previous beam splitter, and vertically incident on the next beam splitter together. Finally, these material beams are mixed together and incident on the mask plate and substrate at a nearly zero angle to form a device with a uniform and high-precision pattern.

[0038] The nozzle of the evaporation source is a material beam forming device, one end of the nozzle is connected to the outlet of the evaporation source (material source) and collects the material beam emitted from the material source. The material beam is reflected or secondarily evaporated by the inner wall of the channel with the heating element arranged in the evaporation source, and enters the vacuum cavity formed by the wall 10 of the film coating chamber at various angles from the narrow outlet.

[0039] The curved reflector is a device having a smooth curved surface continuous with the heating device. The curved reflector is used to shape the material beam emitted from the nozzle into a nearly parallel material beam by reflection. The surface shape of the curved reflector can be a curved surface formed by various curves such as circular arcs, elliptical arcs, parabolas, and cubic curves by rotation, translation, and other operations. Preferably, the curved reflector used for the point source is a paraboloid of revolution reflector, and the curved reflector used for the line source is a slotted paraboloid shaped reflector.

[0040] A planar reflector is a device that has a smooth plane that is continuous with the heating element. A curved reflector can be considered as a planar reflector if the curvature of the surface is relatively small. Planar reflectors are used to change the propagation direction of a material beam, and can reflect material beams emitted from different material sources to different beam splitters arranged in the same longitudinal direction.

[0041] A beam splitter is a device with a heating component and discontinuous smooth planes, which includes multiple reflectors with multi-directional reflecting surfaces. When material beams incident from different directions hit different surfaces of the beam splitter, the material beams are reflected or secondarily evaporated by the discontinuous surfaces of the beam splitter, and finally emitted in the same direction. In order to deposit multiple layers of different materials on a substrate or deposit multiple different materials simultaneously, it is usually necessary to arrange multiple beam splitters on one side of the substrate for thin film deposition and in a direction perpendicular to the substrate. Here, the direction perpendicular to the substrate is called the vertical direction, and the direction parallel to the substrate is called the horizontal direction.

[0042] The surface material of the reflective surface of the curved reflector, the flat reflector, and the beam splitter is one or more composite materials selected from the group consisting of metal, inorganic non-metallic material, and polymer. Preferably, the surface material of the reflective surface of the reflector and the beam splitter is stainless steel, Al2O3, single crystal silicon, diamond coating film, etc.

[0043] The evaporation temperature of the material beam i is Ct(i), and the surface adsorption energy of the material beam i to the reflecting surface material j at absolute zero is E ab Let (i,j).

[0044] The heating element (heat source) is generally a heating wire. The heating temperature is Ct(i) + E ab (i,j) / k B If the heating temperature is lower than that temperature or higher than Ct(i), the material beam i is reflected by the reflector or beam splitter's reflecting surface j and undergoes secondary evaporation. If the heating temperature is lower than Ct(i), the material i is primarily deposited. Here, k B is the Boltzmann constant.

[0045] The incidence angle of the material beam shaped on the substrate by the reflector and beam splitter depends on the surface material, roughness, temperature, curvature shape of the reflector and beam splitter and the size of the nozzle outlet of the material beam. The smaller the roughness of the reflector and beam splitter surface, the higher the temperature, the larger the curvature, and the smaller the nozzle outlet (point source) or narrow line source), the smaller the incidence angle. Figure 5 is a schematic diagram showing several selectable cross-sectional shapes of the beam splitter reflector, with different curvature shapes and orientation angles of the reflective surface.

[0046] The technical effect of the present invention is to provide a coating film with high uniformity and excellent microstructure.

[0047] In order to further understand the objectives, structure, features and functions of the present invention, detailed descriptions in conjunction with embodiments are provided below.

[0048] <About thin film deposition equipment (point source vacuum thermal evaporation film coating equipment)> Figures 1A and 1B are respectively a side view and a top view of a simplified schematic diagram of a point source vacuum thermal evaporation film coating apparatus, in which 10 is a wall of a film coating chamber, 11 is a film coating substrate, 12 is a film coating mask plate, 13 is a heating device, 14 is a reflecting surface, 20 is an evaporation source, 21 is a nozzle, 30 is a curved reflector, 40 is a flat reflector, and 50 is a beam splitter. Here, the structures of 30 curved reflector, 40 flat reflector, and 50 beam splitter are shown in Figures 2A, 2B, 3A, and 3B, respectively.

[0049] Here, the film-coated substrate 11 is a silicon wafer with a diameter of 300 mm, the diameter of the mask plate 12 is 320 mm, the thickness of the mask plate 12 is 5 μm, the aperture size of the mask plate 12 is 5 μm, and the surfaces of all the reflectors are monocrystalline silicon <100> The surface is a rectangular prism with a roughness of less than 0.5 nm. The heating element is a resistance wire. The temperature of the resistance wire needs to be adjusted according to the evaporation temperature and evaporation rate of different materials, as well as the reflection angle of the reflector. The horizontal or vertical orthogonal projection of the curved reflector, flat reflector and beam splitter is 330 mm, and each reflector in the beam splitter is a square prism with a side length of 1 mm, and the beam splitter is installed at an elevation angle of 26.5° to the horizontal direction.

[0050] In Figure 1A, if the thin film to be deposited has a certain pattern, a mask plate with a certain pattern needs to be placed on the thin film deposition side of the substrate, so that the area of ​​the substrate blocked by the mask plate will not have the thin film deposited, but the area cut out by the mask plate will have the thin film deposited. If the thin film to be deposited does not need to be patterned, the mask plate can be removed.

[0051] The dotted lines in Figure 1A show the propagation path of the material beam in the reflector and the beam splitter. When the material in the material evaporation source is heated to the evaporation temperature, the material is continuously ejected from the nozzle in the form of gas or nanoparticles at a certain speed onto the inner surface of the parabolic reflector at various angles, and becomes a nearly parallel material beam after being reflected by the hot parabolic surface, and then deflected by the flat reflector and ejected onto the surface of the beam splitter.

[0052] Figures 3A and 3B are schematic diagrams of the structure of the beam splitter. Figure 3A is a side view of the beam splitter when it is installed in the device at a certain angle. In Figure 3A, reference numeral 51 denotes the beam splitter frame, reference numeral 52 denotes the beam splitter part (beam splitter reflector), reference numeral 13 denotes the heating part (heating device), and reference numeral 14 denotes the reflecting surface. Figure 3B is a schematic plan view of the beam splitter.

[0053] When the vertically propagating material beam is sprayed on the surface of the beam splitter, about half of the material beam is reflected horizontally to the base of the wall of the film coating chamber, and the remaining half of the material beam continues to propagate vertically after being reflected twice, as shown in Figure 4B. When the horizontally propagating material beam is sprayed on the surface of the beam splitter, all the material beam is reflected and propagates vertically, as shown in Figure 4A. At this point, the horizontally and vertically propagating material beams become a mixed vertical material beam after being reflected by the beam splitter, and enter the next stage of the beam splitter, as shown in Figure 4C.

[0054] Figure 1C is a schematic diagram (perspective view from a 45° downward angle) of a thin film deposition apparatus when the evaporation source is a line source. Its operating principle is the same as that of a film coating apparatus by vacuum thermal evaporation. The shapes of the reflector and beam splitter are different. Here, the flat reflector is rectangular in shape, the curved reflector is a slotted paraboloid shape, and the beam splitter is a rectangular device formed by arranging square prism-shaped beam splitter components of the same length.

[0055] <About film coating equipment for molecular beam epitaxy> A simplified schematic diagram (side view) of the structure of a film coating apparatus for molecular beam epitaxy is shown in Figure 1D. Here, reference numeral 61 denotes a molecular beam emission slit, reference numeral 62 denotes a liquid nitrogen cooling shield, and reference numeral 63 denotes a source furnace flange. The material beam emitted from the source furnace flange 63 passes through the emission slit and is incident on the substrate and the mask plate at approximately the same angle.

[0056] Through reflection mixing by the flat reflector 40 and the beam splitter 50, the molecular beams emitted from different material sources are coated or doped onto the substrate at the same small angle, completing the film coating of the substrate.

[0057] In practice, the slits and cooling shields of the molecular beam epitaxy film coating apparatus can function as a point source and a curved reflector, and can emit a material beam in a nearly parallel manner. Therefore, the embodiment of the molecular beam epitaxy film coating apparatus does not need to provide a curved reflector. The other structures and functions can be referred to in the embodiment of the thin film deposition apparatus using a point source, and will not be described further here.

[0058] The thin film deposition apparatus and deposition method of the present invention includes a plurality of reflectors, beam splitters and other components, and can uniformly mix and shape the material beams emitted from one or more gas phase material point sources or line sources into a surface source. The apparatus can be used to manufacture thin films or epitaxy devices with high uniformity and small shadow effect, which can improve the quality of the thin film and reduce the effective size of the microstructure of the device. During the deposition process, each evaporation source 20 emits a material beam 70 through a nozzle 21, each material beam 70 is emitted to a corresponding curved reflector 30, each material beam 70 is reflected to a corresponding flat reflector 40, each flat reflector 40 ejects the corresponding material beam 70 onto the surface of the corresponding beam splitter component 52 of the beam splitter 50, and all the material beams 70 are coated or doped on the substrate 11 after passing through the top beam splitter component 52. When the vertically propagating material beam 70 is injected onto the surface of the corresponding beam splitter part 52 of the beam splitter 50, a part 70 (about half) of the material beam is horizontally reflected to the base of the wall of the film coating chamber, and a part 70 (about the remaining half) of the material beam continues to propagate after being vertically reflected. When the horizontally propagating material beam 70 is injected onto the surface of the corresponding beam splitter part 52 of the beam splitter 50, all of the material beam 70 is reflected and propagates vertically, and the vertically and horizontally propagating material beams 70 are reflected by the beam splitter 50 to become a mixed vertical material beam, which is incident on the top beam splitter part 52, and the material beams 70 emitted from the different evaporation sources 20 are coated or doped on the substrate 11 at the same small angle after passing through the top beam splitter part 52, and then the deposition is completed.

[0059] Although the present invention has been described by way of example with reference to the accompanying drawings, it is clear that the specific implementation of the present invention is not limited to the above-mentioned methods. As long as the method concept and technical solutions of the present invention are used to make various improvements, or the concept and technical solutions of the present invention are directly applied to other cases without improvements, they are all within the protection scope of the present invention. [Explanation of symbols]

[0060] 10. Film coating room wall 11, substrate 12, mask plate 13, heating element 14, reflective surface 20, evaporation source 21, nozzle 30, curved reflector 40, flat reflector 50, beam splitter 51, beam splitter frame 52, beam splitter parts 60. Molecular beam epitaxy film coating equipment 61. Molecular beam emission slit 62. Liquid nitrogen cooling shield 63, source furnace flange 70, material beam

Claims

1. A thin film deposition apparatus including a film coating chamber wall 10, a plurality of evaporation sources 20 arranged in a lower region of the wall 10 of the film coating chamber; a flat reflector 40 arranged in the lower region of the wall 10 of the film coating chamber; a beam splitter 50 disposed in an intermediate region of the wall 10 of the film coating chamber; The beam splitter 50 includes a plurality of beam splitter components 52, each of which is arranged at an acute angle with respect to the horizontal; A plane reflector 40 is further disposed in the horizontal direction of the beam splitter 50, and the plane reflector 40 is disposed at an acute angle with respect to the horizontal direction. A thin film deposition apparatus, characterized in that a heating component is disposed on each of said flat reflector, said curved reflector and said beam splitter component.

2. A curved reflector 30 is disposed corresponding to the position of each of the evaporation sources 20, Or, the evaporation source 20 is a molecular beam epitaxy film coating device 60; 2. The thin film deposition apparatus of claim 1, wherein the molecular beam epitaxy film coating apparatus (60) comprises a molecular beam emission slit (61), a liquid nitrogen cooled shield (62) and a source furnace flange (63).

3. The thin film deposition apparatus of claim 1, characterized in that the substrate 11 and the mask plate 12 are arranged from top to bottom in the upper region of the wall 10 of the film coating chamber, the substrate 11 is a silicon wafer, and the diameter of the mask plate 12 is larger than the diameter of the substrate 11.

4. 4. The thin film deposition apparatus of claim 3, wherein the beam splitter elements of the beam splitter are arranged from top to bottom, and two adjacent beam splitters have an acute angle structure.

5. The thin film deposition apparatus of claim 4, wherein when the curved reflectors 30 corresponding to the positions of the evaporation sources 20 are arranged, each evaporation source 20 includes a nozzle 21, the nozzle 21 of each evaporation source 20 is directed toward one curved reflector 30, and each curved reflector 30 corresponds to one flat reflector 40.

6. 6. The thin film deposition apparatus of claim 5, wherein the planar reflector is rectangular and the curved reflector is a slotted paraboloid in shape.

7. 6. The thin film deposition apparatus of claim 5, wherein one flat reflector 40 corresponding to each curved reflector 30 is parallel to one corresponding beam splitter component 52, each beam splitter component 52 of the beam splitter 50 has a rectangular prism structure, and the angle of each beam splitter 50 with respect to the horizontal direction is less than 30°.

8. 3. A thin film deposition apparatus according to claim 1 or claim 2, characterized in that the heating element (13) is a resistance wire.

9. The thin film deposition apparatus of claim 7, wherein the surfaces of the curved reflector 30 and the flat reflector 40 are surfaces of single crystal silicon 100 having a surface roughness of less than 0.5 nm, and the beam splitter 50 includes a plurality of rectangular prism-shaped beam splitter components 52.

10. 1. A method for thin film deposition comprising: Each evaporation source 20 emits a material beam 70 from a nozzle 21, each material beam 70 is emitted to a corresponding curved reflector 30, each material beam 70 is reflected to a corresponding flat reflector 40, each flat reflector 40 ejects the corresponding material beam 70 onto a surface of a corresponding beam splitter component 52 of the beam splitter 50, and after all the material beams 70 pass through the top beam splitter component 52, the substrate 11 is coated or doped S1; When the vertically propagating material beam 70 is injected onto the surface of the corresponding beam splitter component 52 of the beam splitter 50, a portion of the material beam 70 is horizontally reflected off the base of the wall of the film coating chamber, and a portion of the material beam 70 continues to propagate after being vertically reflected (S2); When a horizontally propagating material beam 70 is injected onto the surface of the corresponding beam splitter component 52 of the beam splitter 50, all of the material beam 70 is reflected and propagated vertically S3; The vertically and horizontally propagating material beams 70 are reflected by the beam splitter 50 into a mixed vertical material beam S4 incident on the top beam splitter component 52; The material beams 70 emitted from the different evaporation sources 20 are coated or doped on the substrate 11 at the same small angle after passing through the top beam splitter component 52, and the deposition is completed after coating or doping S5.

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