Thin film deposition apparatus 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 technical field of semiconductor product manufacturing, and particularly to a thin film deposition apparatus and a thin film deposition method.

Background Art

[0002] In deposition techniques such as vacuum thermal deposition and molecular beam epitaxy, increasing the directional requirements of gaseous material or material particles emitted from the material source (such as an evaporation source) during the thin film deposition process is necessary to improve the uniformity of the fabricated materials and devices and to refine their structure. Currently, most material sources used in vacuum thin film deposition techniques such as vacuum thermal deposition and molecular beam epitaxy are point sources or beam sources. The material beams emitted from these material sources often have different angles of incidence relative to the substrate normal, resulting in shadow effects and non-uniformity of thin film deposition. In vacuum deposition techniques such as vacuum thermal deposition and molecular beam epitaxy, a gaseous material beam (such as an atomic beam, ion beam, molecular beam, or other form of material beam) is emitted from a point source or beam source in a nearly linear manner and flies through 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 upon impact with the substrate and the normal to the substrate. The angle of incidence is typically between 0 and 90°. A smaller angle of incidence improves the quality and uniformity of thin-film deposition and reduces the effective size of the microstructure in thin-film device microstructures. Considering this, surface source technology has attracted considerable attention and has been extensively studied. A surface source refers to a film coating source with a planar structure. Compared to point or line sources, atomic beams, molecular beams, or material particles emitted from a surface source can be incident perpendicularly to the substrate, resulting in an angle of incidence of 0°. Currently, surface source-based methods in the field of vacuum thermal evaporation generally involve first depositing a point or line source material onto a low-temperature intermediate substrate, and then heating the intermediate substrate toward the final substrate to deposit the entire material film onto the final substrate. These surface source technologies are fraught with difficulties, are inefficient and costly, making rapid widespread adoption challenging.

[0003] In the prior art, titled "Thin Film Deposition Apparatus and Thin Film Deposition Method" (Patent Document 1), the thin film deposition apparatus of the said art includes a thin film deposition chamber, which includes a cavity housing surrounding the cavity of the thin film deposition chamber, a target bracket located in the center of the cavity and used to house a target consisting of component A, a substrate platform located in the center of the cavity and positioned opposite the target bracket, a laser output port located on the side of the cavity housing, tilted away from the target bracket, for irradiating a target on the target bracket with a laser to generate a plasma plume, and a beam source reactor interface located on the side of the cavity housing, tilted away from the substrate platform, for injecting a molecular beam stream consisting of component B. The laser output port and the beam source reactor interface are simultaneously injected with a laser and a molecular beam stream. The present invention effectively avoids mutual interference between the film deposition process by pulsed laser deposition and the film deposition process by molecular beam epitaxy, and can produce higher quality thin films that cannot be manufactured by the prior art.

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

[0005] [Patent Document 1] Chinese Patent Application Publication No. 103103480 Specification [Overview of the project] [Problems that the invention aims to solve]

[0006] The technical problem that this invention aims to solve is to provide a thin-film deposition apparatus that is simple in structure, low in cost, convenient to use, highly reliable, ensures high directionality of gaseous material or material particles released from a material source during the thin-film deposition process, converts point sources or radiation sources within the apparatus into surface sources in various deposition techniques such as vacuum thermal deposition and molecular beam epitaxy, eliminates shadow effects, improves the uniformity of thin-film deposition, and ultimately improves product performance. [Means for solving the problem]

[0007] To address the above technical challenges, the technical solutions provided in this disclosure are as follows:

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

[0009] In the upper region of the wall of the film coating chamber, the substrate and mask plate are arranged from top to bottom, the substrate being a silicon wafer, and the diameter of the mask plate being larger than the diameter 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 evaporation source includes a nozzle, the nozzle of each evaporation source is directed towards one curved reflector, and each curved reflector corresponds to one planar reflector.

[0012] Each curved reflector is paired with a corresponding planar reflector, which is parallel to a corresponding beam splitter component. Each beam splitter component has a rectangular prism structure, and the angle of each beam splitter component with respect to the horizontal is less than 30°.

[0013] The aforementioned heating component is a resistance wire.

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

[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 cooling 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 that is simple in steps, low in cost, convenient and reliable to use, ensures high directionality of gaseous material or material particles released from a material source during the thin film deposition process, converts point or radiation sources in the apparatus into surface sources in various deposition techniques such as vacuum thermal deposition and molecular beam epitaxy, eliminates shadow effects, improves the uniformity of thin film deposition, and ultimately improves product performance. The thin film deposition method comprises 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 toward a corresponding planar reflector, each planar reflector sprays the corresponding material beam onto the surface of the corresponding beam splitter component of the beam splitter, and all material beams, after passing through the uppermost beam splitter component, are coated or doped onto the substrate. In step S2, when a vertically propagating material beam is injected onto the surface of the corresponding beam splitter component of the beam splitter, a portion (about half) of the material beam is reflected horizontally off the base of the wall of the film coating chamber, and a portion (about the remaining half) of the material beam continues to propagate even after being reflected vertically. In step S3, when a material beam propagating horizontally is injected onto the surface of the corresponding beam splitter component of the beam splitter, all of the material beam is reflected and propagates vertically. In step S4, the material beams propagating in the vertical and horizontal directions are reflected by the beam splitter to become a mixed vertical material beam, which is then incident on the uppermost beam splitter component. In step S5, the material beams emitted from the different evaporation sources pass through the uppermost beam splitter component and are then irradiated onto the substrate at the same small angle, where they are coated or doped and then deposited. [Effects of the Invention]

[0017] The technical solution of the present invention has the following operating principle and beneficial effects.

[0018] According to the thin film deposition apparatus and its deposition method of the present invention, the apparatus of the present invention includes a plurality of reflectors, a beam splitter, and other components, and can uniformly mix the material beams emitted from one or more vapor-phase material point sources or line sources and form them into a surface source. The apparatus can be used for manufacturing thin films or epitaxial devices with high uniformity and little influence of shadow, can improve the quality of the thin film, and can reduce the effective size of the fine structure of the device. During the deposition process, each evaporation source 20 emits a material beam 70 from the nozzle 21, each material beam is emitted towards the corresponding curved reflector 30, each material beam 70 is reflected by the corresponding planar reflector, each planar reflector 40 injects 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 uppermost beam splitter component. When injecting the material beam propagating in the vertical direction onto the surface of the corresponding beam splitter component 52 of the beam splitter ⑤, 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 reflected vertically. When the material beam propagating in the horizontal direction is injected onto the surface of the corresponding beam splitter component of the beam splitter, all of the material beam is reflected and propagated in the vertical direction. The material beams propagating in the vertical and horizontal directions are reflected by the beam splitter to form a mixed vertical material beam and are incident on the uppermost beam splitter component. The material beams emitted from different evaporation sources are coated or doped on the substrate at the same small angle after passing through the uppermost beam splitter component, and the deposition is completed after the coating or doping.

Brief Description of the Drawings

[0019] The content shown in the drawings attached to this specification and the reference numerals in the drawings will be briefly described below.

[0020] [Figure 1A] It is a schematic side view of the thin film deposition apparatus according to the present invention. [Figure 1B]It is a schematic plan view of a thin film deposition apparatus when the evaporation source is a point source. [Figure 1C] It is a schematic perspective view of a thin film deposition apparatus when the evaporation source is a line source, viewed from an angle of 45° downward. [Figure 1D] It is a schematic side view of a thin film deposition apparatus when the evaporation source is a molecular beam epitaxy deposition apparatus. [Figure 2A] It is a schematic structural view of a plane reflector. [Figure 2B] It is a schematic structural view of a curved reflector. [Figure 3A] It is a schematic side view of a beam splitter (point source beam splitter). [[ID=十七]]<ねんろくの1つの [Figure 3B] It is a schematic plan view of a point source beam splitter. [Figure 4A] It is a diagram showing the principle by which a beam splitter reflects a material beam in the horizontal direction (lateral direction). [Figure 4B] It is a diagram showing the principle by which a beam splitter reflects a material beam in the vertical direction (longitudinal direction). [Figure 4C] It is a diagram showing the operating principle of a thin film deposition apparatus. [Figure 5] It is a schematic view of an arbitrary cross-sectional shape of a beam splitter component (reflector) of a beam splitter.

Embodiments for Carrying Out the Invention

[0021] Regarding specific embodiments of the present invention, for example, the shapes and structures of various related components, the mutual positions and connection relationships between various components, the functions and operating principles of various components, etc., will be further described in detail below through the description of the embodiments while referring to the accompanying drawings.

[0022] As shown in Figures 1A to 5, the present invention provides a thin film deposition apparatus that includes a wall 10 of a film coating chamber. The wall 10 of the film coating chamber is divided into an upper region, an intermediate 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 curved reflector 30 is arranged corresponding to the position of each evaporation source 20, a planar 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 intermediate 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 planar reflector 40 is arranged horizontally to the beam splitter 50. The planar reflector 40 is arranged at an acute angle with respect to the horizontal direction. Heating components 13 are arranged in the planar reflector 40, the curved reflector 30, and the beam splitter component 52, respectively. The above structure provides an improved technical solution to address the shortcomings of the prior art. The deposition apparatus as a whole includes multiple reflectors, beam splitters, and other components, and can uniformly mix material beams emitted from one or more gas-phase point sources or radiation sources and form them into a surface source. The apparatus can be used to manufacture thin films or epitaxy devices with high uniformity and minimal shadow effects, improving the quality of the thin film and reducing the effective size of the device's 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 planar reflector 40, each planar reflector 40 sprays the corresponding material beam 70 onto the surface of the corresponding beam splitter component 52 of the beam splitter 50, and all material beams 70, after passing through the uppermost beam splitter component 52, are coated or doped onto the substrate 11. 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 (about half) is reflected horizontally off the base of the wall of the film coating chamber, while a portion of the material beam 70 (about the remaining half) continues to propagate after being reflected vertically.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 propagates vertically. The vertically and horizontally propagating material beams 70 are reflected and mixed by the beam splitter 50 to form a vertical material beam, which is then incident on the uppermost beam splitter component 52. After the material beams 70 emitted from different evaporation sources 20 pass through the uppermost beam splitter component 52, they are coated or doped onto the substrate 11 at the same small angle, and deposition is completed after coating or doping. The thin film deposition apparatus and deposition method of the present invention are low-cost and convenient to use, ensure high directionality of gaseous material or material particles emitted from the material source during the thin film deposition process, and can convert point sources or line sources within the apparatus into surface sources in various deposition techniques such as vacuum thermal deposition and molecular beam epitaxy, eliminating the effects of shadows, improving deposition uniformity, and improving product performance.

[0023] In the upper region of the wall 10 of the film coating chamber, a substrate 11 and a mask plate 12 are arranged from top to bottom. The substrate 11 is a silicon wafer, and the diameter of the mask plate 12 is larger than the diameter of the substrate 11. In the above structure, when deposition is performed, the entire deposition process is carried out based on the wall 10 of the film coating chamber. The substrate and mask plate are placed in the upper part inside the wall 10 of the film coating chamber, and the lower material beam coats from top to bottom to complete the process. If a thin film awaiting deposition with a specific pattern structure needs to be deposited, a mask plate 12 with a specific pattern is placed on the side of the substrate 11 where the thin film is to be deposited. Deposition does not occur in the area of ​​the substrate 11 blocked by the mask plate 12, and deposition occurs in the area cut out by the mask plate 12 to form a pattern. If pattern formation is not required on the deposited thin film, the mask plate can be removed.

[0024] The beam splitter components 52 of the beam splitter 50 are arranged from top to bottom, and two adjacent beam splitter components 52 have an acute-angle structure. Each evaporation source 0 is equipped with a nozzle 21, and the nozzle 21 of each evaporation source 20 is directed toward one curved reflector 30, and each curved reflector 30 corresponds to one planar reflector 40. The planar reflector 40 corresponding to each curved reflector 30 is parallel to the 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 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 ejected from the nozzle into the inner surface of the corresponding curved reflector at various angles and at a specific velocity in the form of gas or nanoparticles. After being reflected by the parabolic surface of the curved reflector, the material beam becomes nearly planar and is ejected onto the surface of the planar reflector, where it is deflected and ejected onto the surface of the beam splitter. Finally, the material beams 70 emitted from the different evaporation sources 20 pass through the uppermost beam splitter component 52 and are then coated or doped onto the substrate 11 at the same small angle, with deposition completed after coating or doping.

[0025] The heating component 13 is a resistance wire. In the above structure, since the heating wire is used for heating, the curved reflector, plane reflector, and beam splitter all become high-temperature structures, promoting the reflection of the material beam.

[0026] The surfaces of the curved reflector 30 and the planar reflector 40 are single-crystal silicon (100) surfaces with a surface roughness less than 0.5 nm, the planar reflector 40 is rectangular, the curved reflector 30 has a slotted parabolic shape, and the beam splitter 50 is composed of a plurality of rectangular prism-shaped beam splitter components 52 arranged in a row. 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 that is simple in steps, low in cost, convenient to use and highly reliable, ensures high directionality of gaseous material or material particles released from a material source during the thin film deposition process, converts point or radiation sources in the apparatus into surface sources in various deposition techniques such as vacuum thermal deposition and molecular beam epitaxy, eliminates shadow effects, improves the uniformity of thin film deposition, and ultimately improves product performance. The deposition steps of the said thin film deposition method include the following:

[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 toward a corresponding planar reflector 40, each planar reflector 40 sprays the corresponding material beam 70 onto the surface of the corresponding beam splitter component 52 of the beam splitter 50, and all the material beam 70, after passing through the uppermost beam splitter component 52, is coated or doped onto the substrate 11.

[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 of the material beam 70 (about half) is reflected horizontally off the base of the wall of the film coating chamber, and a portion of the material beam 70 (about the remaining half) continues to propagate after being reflected vertically.

[0030] S3. When the 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 propagates vertically.

[0031] S4. The material beams 70 propagating in the vertical and horizontal directions are reflected and mixed by the beam splitter 50 to form a vertical material beam, which is then incident on the uppermost beam splitter component 52.

[0032] S5. The material beams 70 emitted from the different evaporation sources 20 pass through the uppermost beam splitter component 52 and are then coated or doped onto the substrate 11 at the same small angle, after which deposition is completed.

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

[0034] The technical problems addressed by this 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 sources or beam sources. The angle of incidence of the material beam emitted from these sources during deposition onto the substrate is generally not zero, and the angle of incidence at different locations on the substrate generally differs, resulting in reduced uniformity of the deposited thin film. Furthermore, the effective size of the microstructure in thin-film devices increases due to the shadow effect. In the above techniques, it is difficult to uniformly mix materials emitted from different material sources.

[0036] The technical solution of the present invention for solving the technical problems is as follows:

[0037] An evaporation source with a heating component, a curved reflector, a planar reflector, and a beam splitter are arranged. Material beams emitted from different point or linear material sources are shaped into nearly parallel material beams by the curved reflector, their paths are altered by the planar reflector, and then emitted into a series of longitudinally arranged beam splitters, where they are mixed with the material beam emitted from the previous beam splitter and incident together longitudinally into the next stage of beam splitters. Finally, these material beams are mixed together and incident onto the mask plate and substrate at nearly zero angle, forming a device with a uniform and high-precision pattern.

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

[0039] A curved reflector is a device having a smooth curved surface continuous with a heating device. The curved reflector is used to shape a material beam emitted from a nozzle into a substantially 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 through rotation, translation, and other operations. Preferably, a curved reflector used for a point source is a rotating parabolic reflector, and a curved reflector used for a line source is a slotted parabolic reflector.

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

[0041] A beam splitter is a device having a heating component and a discontinuous smooth plane, and includes multiple reflectors with multidirectional reflective surfaces. When material beams incident from different directions strike different surfaces of the beam splitter, the material beams are reflected or secondarily evaporated by the discontinuous surfaces of the beam splitter and ultimately emitted in the same direction. To deposit different materials in multiple layers on a substrate, or to 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 perpendicular to the substrate. Here, the direction perpendicular to the substrate is called the longitudinal direction, and the direction parallel to the substrate is called the transverse direction.

[0042] The surface material of the reflective surface of a curved reflector, a planar reflector, or a beam splitter is a composite material of one or more materials selected from metals, inorganic nonmetallic materials, and polymers. Preferably, the surface material of the reflective surface of the reflector and beam splitter is stainless steel, Al2O3, single-crystal silicon, a diamond coating film, etc.

[0043] Let Ct(i) be the evaporation temperature of the material beam material i, and let E be the surface adsorption energy of the material beam material i to the reflective surface material j at absolute zero. ab Let (i,j) be the coordinates.

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

[0045] The angle of incidence of the material beam formed on the substrate by the reflector and beam splitter varies depending on the surface material, roughness, temperature, curvature of the reflector and beam splitter, and the size of the material beam nozzle exit. The angle of incidence decreases as the surface roughness of the reflector and beam splitter decreases, the temperature increases, the curvature increases, and the nozzle exit becomes smaller (point source or narrow source). Figure 5 is a schematic diagram showing several selectable cross-sectional shapes of a beam splitter reflector, which differ in the curvature of the reflective surface and the orientation angle.

[0046] The technical advantage of this invention is that it provides a coating film with high uniformity and excellent microstructure.

[0047] To further understand the purpose, structure, features, and function of the present invention, a detailed description in conjunction with embodiments is provided below.

[0048] <About the Thin Film Deposition System (Point Source Vacuum Thermal Evaporation Film Coating System)> Figures 1A and 1B are a simplified schematic side view and a plan view of a point source vacuum thermal deposition film coating apparatus, respectively. In the figures, reference numeral 10 denotes the wall of the film coating chamber, reference numeral 11 denotes the film coating substrate, reference numeral 12 denotes the film coating mask plate, reference numeral 13 denotes the heating device, reference numeral 14 denotes the reflective surface, reference numeral 20 denotes the evaporation source, reference numeral 21 denotes the nozzle, reference numeral 30 denotes the curved reflector, reference numeral 40 denotes the planar reflector, and reference numeral 50 denotes the beam splitter. The structures of the 30 curved reflector, 40 planar 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 mask plate 12 has a diameter of 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 surface of all reflectors is single-crystal silicon. <100> The surface has a surface roughness less than 0.5 nm. The heating component 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 orthographic projection in the lateral or vertical direction of the curved reflector, planar reflector, and beam splitter is 330 mm, each reflector in the beam splitter is a rectangular prism with a side length of 1 mm, and the beam splitter is installed at an elevation angle of 26.5° with respect to the lateral direction.

[0050] In Figure 1A, if the thin film awaiting deposition has a specific pattern, a mask plate with the specific pattern must be placed on the thin film deposition side of the substrate. As a result, the thin film will not be deposited in the areas of the substrate blocked by the mask plate, but will be deposited in the areas cut out by the mask plate. If the thin film to be deposited does not require pattern formation, 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 beam splitter. Once the material in the material evaporation source is heated to its evaporation temperature, the material is continuously ejected from the nozzle at a specific velocity and at various angles onto the inner surface of the parabolic reflector in the form of a gas or nanoparticles. After being reflected by the hot parabolic surface, it becomes a nearly parallel material beam, which is then deflected by the plane reflector and ejected onto the surface of the beam splitter.

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

[0053] When a longitudinally propagating material beam is ejected onto the surface of the beam splitter, approximately half of the material beam is reflected laterally off the base of the film coating chamber wall, as shown in Figure 4B, while the remaining half of the material beam is reflected twice and continues to propagate longitudinally. When a transversely propagating material beam is ejected onto the surface of the beam splitter, all of the material beam is reflected and propagates longitudinally, as shown in Figure 4A. At this point, the transversely and longitudinally propagating material beams, after being reflected by the beam splitter, become a mixed longitudinal material beam 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 downward 45° angle) of a thin film deposition apparatus when the evaporation source is a radiation source. Its operating principle is the same as that of a film coating apparatus using vacuum thermal evaporation. The shapes of the reflector and beam splitter are different. Here, the planar reflector is rectangular, the curved reflector is a slotted parabolic shape, and the beam splitter is a rectangular device formed by arranging rectangular prism-shaped beam splitter components of the same length.

[0055] <About the film coating system for molecular beam epitaxy> Figure 1D shows a simplified schematic diagram (side view) of the structure of a molecular beam epitaxy film coating apparatus. Here, reference numeral 61 denotes the molecular beam emission slit, reference numeral 62 denotes the liquid nitrogen cooling shield, and reference numeral 63 denotes the 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 mask plate at approximately the same angle.

[0056] The reflection mixing of the plane reflector 40 and the beam splitter 50 coats or dops the substrate with molecular beams emitted from different material sources at the same small angle, completing the film coating of the substrate.

[0057] In practical terms, the slits and cooling shields of a molecular beam epitaxy film coating apparatus function the same as a point source and a curved reflector, allowing the material beam to be emitted nearly parallel to the surface. Therefore, in embodiments of molecular beam epitaxy film coating apparatuses, there is no need to provide a curved reflector. Other structures and their functions can be found in the examples of thin-film deposition apparatuses employing point sources, and will not be explained further here.

[0058] The present invention relates to a thin film deposition apparatus and deposition method comprising a plurality of reflectors, beam splitters, and other components, which can uniformly mix material beams emitted from one or more gas-phase material point sources or radiation sources and form them into a surface source. The apparatus can be used to manufacture thin films or epitaxy devices with high uniformity and minimal shadow effects, improving the quality of the thin film and reducing the effective size of the device's 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 planar reflector 40, each planar reflector 40 sprays the corresponding material beam 70 onto the surface of the corresponding beam splitter component 52 of the beam splitter 50, and all material beams 70, after passing through the uppermost beam splitter component 52, are coated or doped onto the substrate 11. When a 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 (about half) is reflected horizontally off the base of the wall of the film coating chamber, and a portion of the material beam 70 (about the remaining half) continues to propagate after being reflected vertically. 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 propagates vertically, and the vertically and horizontally propagating material beams 70 are reflected and mixed at the beam splitter 50 to form a vertical material beam which is then incident on the uppermost beam splitter component 52, and the material beams 70 emitted from the different evaporation sources 20 pass through the uppermost beam splitter component 52 and are then coated or doped onto the substrate 11 at the same small angle, after which deposition is completed.

[0059] Although the present invention has been described illustratively in conjunction with the accompanying drawings, it is clear that the specific implementation of the present invention is not limited to the methods described above. Any improvements made to the method concept and technical solutions of the present invention, or any direct application of the concept and technical solutions of the present invention without modification, are all within the scope of protection of the present invention. [Explanation of Symbols]

[0060] 10. Wall of the film coating room 11. Circuit board 12. Mask plate 13. Heating component 14. Reflective surface 20. Evaporation source 21. Nozzle 30. Curved reflector 40. Planar reflector 50. Beam splitter 51. Beam splitter frame 52. Beam splitter components 60. Molecular beam epitaxy film coating apparatus 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 wall (10) of a film coating chamber, A plurality of evaporation sources (20) and a curved reflector (30) are arranged in the lower region of the wall (10) of the film coating chamber, A planar reflector (40) is positioned in the lower region of the wall (10) of the film coating chamber, The intermediate region of the wall (10) of the film coating chamber includes a plurality of beam splitters (50) arranged in a vertical order, Each of the beam splitters (50) includes a plurality of beam splitter components (52), and each of the beam splitter components (52) is arranged at an acute angle with respect to the horizontal direction. A planar reflector (40) is further arranged horizontally in the beam splitter (50), and the planar reflector (40) is positioned at an acute angle with respect to the horizontal direction. A heating component (13) is provided in each of the planar reflector (40), the curved reflector (30), and the beam splitter component (52). The heating component (13) within the curved reflector (30) is used to further redirect the material beam (70) emitted from the evaporation source (20) to form an approximately planar material beam, and to spray it into the planar reflector (40). The heating component (13) within the plane reflector (40) in the intermediate region is used to further redirect the material beam injected into the plane reflector (40) to form an approximately planar material beam, and to inject it into a beam splitter (50) located in the same horizontal direction. The heating component (13) within the planar reflector (40) in the lower region is used to further redirect the material beam injected into the planar reflector (40) to form an approximately planar material beam, and to inject it into a beam splitter (50) located in the same vertical direction. The heating component (13) within the beam splitter component (52) is used to convert the material beam injected into the beam splitter component (52) into an approximately planar material beam and to inject it vertically upward. A curved reflector (30) corresponding to the position of each evaporation source (20) is arranged. In the upper region of the wall (10) of the film coating chamber, the substrate (11) is positioned above, and the mask plate (12) is positioned directly below the substrate (11). The substrate (11) is a silicon wafer, and the diameter of the mask plate (12) is larger than the diameter of the substrate (11). The multiple beam splitter components (52) of each beam splitter (50) are arranged in a linear fashion in sequence, and two adjacent beam splitters (50) have an acute-angle structure. When 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 planar reflector (40). The planar reflector (40) is rectangular, the curved reflector (30) has a slotted parabolic shape, 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 is less than 30°. The reflector (40) positioned horizontally on the beam splitter (50) is parallel to the beam splitter (50), The angle between the extension of the plane reflector (40) located in the lower region of the wall (10) of the film coating chamber and the extension of the plane reflector (40) located in the intermediate region is the same as the angle formed by two adjacent beam splitters (50). A planar reflector (40) located in the lower region of the wall (10) of the film coating chamber is used to receive the horizontal material beam (70) ejected from the corresponding curved reflector (30) and to eject it onto the surface of the corresponding beam splitter component (52) of the nearest vertical beam splitter (50). A horizontally positioned planar reflector (40) of the beam splitter (50) receives the vertical material beam (70) ejected from the corresponding curved reflector (30) and is used to eject it onto the surface of the corresponding beam splitter component (52) of the beam splitter (50) that is closest to it in the horizontal direction. The material beam (70) that is ejected perpendicularly to the surface of the corresponding beam splitter component (52) in the nearest beam splitter (50) is ejected to an adjacent beam splitter component (52) in the same beam splitter (50), and further ejected vertically upward by the adjacent beam splitter component (52) to the surface of the corresponding beam splitter component (52) in the adjacent beam splitter (50). A thin film deposition apparatus characterized in that a material beam (70) sprayed horizontally onto the surface of the corresponding beam splitter component (52) of the nearest beam splitter (50) is sprayed vertically upward onto the surface of the corresponding beam splitter component (52) in the adjacent beam splitter (50).

2. The thin film deposition apparatus according to claim 1, characterized in that the heating component (13) is a resistance wire.

3. The thin film deposition apparatus according to claim 2, characterized in that the surfaces of the curved reflector (30) and the planar reflector (40) are surfaces of single-crystal silicon (100) with a surface roughness of less than 0.5 nm.

4. A thin film deposition method applicable to the thin film deposition apparatus described in claim 1, Step 1 involves each evaporation source (20) emitting a material beam (70) from a nozzle (21), emitting each material beam (70) to a corresponding curved reflector (30), each material beam (70) being reflected by a corresponding planar reflector (40), each planar reflector (40) spraying the corresponding material beam (70) onto the surface of the corresponding beam splitter component (52) of the beam splitter (50), and after all the material beams (70) have passed through the uppermost beam splitter component (52), the substrate (11) being coated or doped. Step 2: When a vertically propagating material beam (70) is sprayed onto the surface of the corresponding beam splitter component (52) of the beam splitter (50), a portion of the material beam (70) is reflected horizontally from the wall (10) of the film coating chamber, and a portion of the material beam (70) continues to propagate even after being reflected vertically. Step 3, 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. Step 4 involves the material beam (70) propagating in the vertical and horizontal directions being reflected by the beam splitter (50) to become a mixed vertical material beam, which is then incident on the uppermost beam splitter component (52), A thin film deposition method characterized by comprising step 5, in which a material beam (70) emitted from different evaporation sources (20) passes through the uppermost beam splitter component (52) and is then coated or doped onto a substrate (11) at the same small angle, and deposition is completed after coating or doping.

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