CN118222984B

CN118222984B - Linear evaporation source for downward evaporation

Info

Publication number: CN118222984B
Application number: CN202410054143.4A
Authority: CN
Inventors: 闫风
Original assignee: Beijing North Hongrui Technology Co ltd
Current assignee: Beijing North Hongrui Technology Co ltd
Priority date: 2024-01-15
Filing date: 2024-01-15
Publication date: 2024-10-18
Anticipated expiration: 2044-01-15
Also published as: CN118222984A

Abstract

The invention relates to a linear evaporation source for downward evaporation, belongs to the technical field of photovoltaic coating, and aims to solve the problems that the existing linear evaporation source for downward evaporation is poor in material uniformity, the requirement of large-breadth coating is difficult to realize, the temperature and the coating process are difficult to control, the production cost is high, the efficiency is low and the like. The linear evaporation source of the invention can realize downward evaporation coating, is suitable for coating wide and large base materials, when materials are heated in the material crucible to generate vapor, the vapor can not be discharged from the upper part of the outer crucible because the outer crucible is of a sealed structure, because the lower end of the outer crucible is provided with a plurality of nozzles, vapor can be discharged through the nozzles after passing through the flow-guiding gas-homogenizing plate, and a plurality of holes are formed in the flow-guiding gas-homogenizing plate, so that the vapor can be more uniformly discharged through the nozzles for coating.

Description

Linear evaporation source for downward evaporation

Technical Field

The invention relates to the technical field of photovoltaic coating, in particular to a linear evaporation source for downward evaporation.

Background

There are many technical implementations of the film layer in the vacuum coating industry, and evaporation coating is one of them, the material is heated to the evaporation process temperature to change the functional material into a gaseous state, and the functional material is deposited on the substrate to be coated, where the substrate to be coated may be flexible metal, inorganic material or organic material, or may be non-flexible silicon wafer, glass, etc. The application fields of photovoltaic industry, semiconductor industry and the like and the mass production of materials generally adopt evaporation coating.

The evaporation source can be classified into a point evaporation source, a linear evaporation source, and a surface evaporation source according to the structure. The general coating efficiency or film thickness uniformity of the point evaporation source is limited by the structure. The linear evaporation source is simply a single structure formed by integrating a plurality of spot evaporation sources in the width direction, and can achieve mass production efficiency or productivity in terms of film coating efficiency and film thickness uniformity. The planar evaporation source is formed by visually combining a plurality of linear evaporation sources in parallel along the movement direction of the substrate according to the throughput.

The workpiece to be plated is generally called a SUBSTRATE, and the english name SUBSTRATE, the SUBSTRATE placement and the movement direction can be divided into two types, horizontal and vertical. The vertical structure can realize the mass production of the coating breadth in principle, can improve the productivity by increasing the coating breadth, has no shielding problem of evaporation of the film material caused by the reinforcing structure due to the increase of the coating breadth, is only technically complicated and has higher overall cost, and can theoretically coat the coating with high proportion and even theoretically full area. The flexible substrate with the horizontal structure does not need a supporting structure in the upward and downward coating directions due to the presence of on-line tension, and can be coated in a theoretically high proportion or even a theoretically full area. If the substrate with the horizontal flat plate structure is coated upwards, the middle part of the substrate generates larger and larger bending deformation along with the increase of the width, and a reinforcing structure is necessarily arranged at a required position, so that two conditions are caused: firstly, the film cannot be coated in a high proportion to the whole area, and secondly, the strengthening position can influence the film coating quality and effect of the peripheral area, so that the area proportion of qualified products is reduced. This occurs after the overall width of the substrate, such as a monolith substrate and a plurality of wafers, has reached a certain level.

The flat plate type coating process is most widely applied in industries such as photovoltaics, and the increase of the width to increase the productivity and the product competitiveness is a necessary technical path. If this way is limited, it will directly cause the interruption of the iterative upgrade of the device, resulting in a reduction in the cost performance of the technology and device, and even more in the end of the life cycle of the technology.

The existing technology and structure for realizing material evaporation are that evaporation materials are placed in containers in different forms, the evaporation materials are heated by various applicable heating modes such as resistance heating, electron beam heating, induction heating and laser heating to be melted and evaporated or sublimated, most of the structures are that the movement direction of the evaporation materials is upward, even if some designs are used for carrying out full-path temperature control to enable the evaporation materials to be supplied from a farther place to realize downward evaporation, but the technical controllability or reliability is insufficient due to structural complexity, the uniformity of the evaporation materials is not controlled, the wide application is inconvenient, the iteration is inconvenient to increase the width of a coating film, and the technology cannot be applied to the photovoltaic industry which is very sensitive to cost and cost performance.

Disclosure of Invention

In view of the above analysis, the present invention aims to provide a linear evaporation source for downward evaporation, which is used for solving one of the problems of poor uniformity of materials, difficult control of temperature and coating process, difficult realization of coating with larger width, high production cost, low efficiency, etc. of the conventional linear evaporation source for downward evaporation.

In order to achieve the above purpose, the present invention adopts the following technical scheme:

The utility model provides a linear evaporation source of downward evaporation, includes supporting structure, outer crucible and the material crucible that cover in proper order from outside to inside, outer crucible upper end sealing connection have outer crucible apron, outer crucible in top-down be provided with crucible backup pad and at least one have porous water conservancy diversion even gas board, the material crucible place the crucible backup pad on, outer crucible with supporting structure between be provided with the heater, outer crucible lower extreme be provided with a plurality of nozzles that are used for spouting the steam to the substrate, the supporting structure bottom be provided with the open pore structure that is used for the nozzle to stretch out.

Further, the crucible supporting plate and the diversion gas homogenizing plate are movably connected with the outer crucible.

Further, the inner diameter of the outer crucible is the same or gradually decreases from top to bottom.

Further, the material crucible is provided with one or more material crucibles, the upper end of the material crucible is provided with a material crucible diversion cover plate, and the material crucible diversion cover plate is provided with a plurality of diversion holes.

Further, the heater includes an upper side heater and/or a lower side heater arranged in a vertical direction.

Further, the heater also comprises an upper heater arranged on the cover plate of the supporting structure or the cover plate of the outer crucible.

Further, the heater also comprises a nozzle heater arranged on the inner side or the outer side of the bottom of the outer crucible.

Further, the upper heater, the lower heater and the nozzle heater are the same or different in shape.

Further, an inner heat insulation structure is arranged between the upper side heater and the lower side heater.

Further, the included angle between the nozzle and the horizontal direction is alpha, wherein alpha is more than 0 degrees and less than or equal to 90 degrees.

Further, the nozzles are arranged in one or more rows.

Further, the supporting structure is sleeved inside the heat insulation device.

Further, the heat insulation device consists of an upper heat insulation structure, a side part and a lower heat insulation structure.

Further, the linear evaporation source is also electrically connected with a coating detection unit.

Compared with the prior art, the invention has at least one of the following beneficial effects:

(1) The linear evaporation source can realize downward evaporation coating, is suitable for wide and large-width substrate coating, and when materials are heated in the material crucible to generate steam, the steam cannot be discharged from the upper part of the outer crucible due to the sealed structure of the outer crucible, and the steam can be discharged through the nozzles after passing through the diversion gas-homogenizing plate, and the diversion gas-homogenizing plate is provided with a plurality of holes, so that the steam can be more uniformly discharged through the nozzles for coating;

(2) The inner diameter of the outer crucible is gradually reduced from top to bottom, and the steam is uniformly distributed step by step from top to bottom by matching with the diversion gas distribution plate, so that the nozzle can spray uniform steam, the film coating is uniform, and the efficiency is higher;

(3) The invention adopts the multi-stage gas-homogenizing flow guide plate and combines the upper heater, the upper side heater, the lower side heater and the nozzle heater for combined use, and the process requirements of uniformity and the like can be more easily met through the adaptation of the number of gas-homogenizing layers and the heaters. The method can be widely applied from low temperature to about 1500 ℃, is not only suitable for medium and low temperature materials such as organic matters and the like, but also used for metal materials such as silver, copper, aluminum and the like, and has much wider applicability for evaporation materials compared with other evaporation technologies;

(4) The evaporation source can realize adjustment of different heating temperatures by selecting the materials of the heater and each part, when the temperature is lower than 700-800 ℃, the proportion of the metal materials and the metal armor heater which are applied to the materials is very high, and when the heating temperature is higher than 700-800 ℃ and lower than 1500 ℃, the materials are selected from high-temperature materials such as ceramic, graphite, tungsten, molybdenum, tantalum, niobium refractory metals and the like;

(5) The evaporation source works in a vacuum environment, and a specific pressure value is set according to the process requirement, so that the evaporation source can be applied to industries such as photovoltaics and the like, and the process and productivity upgrading requirements of larger and larger coating widths are met; when the evaporation source disclosed by the invention is used for coating, the thickness of the coating is uniform, and the coating efficiency is higher.

In the invention, the technical schemes can be mutually combined to realize more preferable combination schemes. Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and drawings.

Drawings

The drawings are only for purposes of illustrating particular embodiments and are not to be construed as limiting the invention, like reference numerals being used to refer to like parts throughout the several views.

FIG. 1 is an overall sectional view of a linear evaporation source according to the present invention;

FIG. 2 is a front sectional view of an assembled linear evaporation source according to the present invention;

FIG. 3 is an assembled cross-sectional view of an outer crucible and a deflector plate according to the present invention;

FIG. 4 is a schematic diagram showing the flow direction of evaporation gas in a linear evaporation source according to the present invention;

FIG. 5 is a schematic view of a multi-row crucible and multi-row nozzle of the present invention;

FIG. 6 is a schematic view of a nozzle of the present invention angled obliquely downward from the outer crucible;

FIG. 7 is a schematic view of a heater according to the present invention;

FIG. 8 is a schematic view of a heater according to the present invention;

FIG. 9 is a schematic view of a heater according to the present invention;

FIG. 10 is a schematic view of a heater according to the present invention;

FIG. 11 is a schematic diagram showing a cross-sectional arrangement of a heater in an evaporation source according to the present invention;

FIG. 12 is a schematic diagram showing a cross-sectional arrangement of a heater in another evaporation source according to the present invention;

FIG. 13 is a schematic view of a flow guiding and homogenizing plate according to the present invention;

FIG. 14 is a schematic view of a crucible support plate structure according to the present invention;

FIG. 15 is a schematic view of an outer crucible assembly of the present invention;

FIG. 16 is a schematic view of an outer crucible assembly of the present invention.

Reference numerals:

1-upper heat insulation structure, 2-support structure cover plate, 3-upper heater, 4-outer crucible cover plate, 5-material crucible diversion cover plate, 6-material crucible, 7-outer crucible, 8-upper side heater, 9-support structure, 10-side and lower heat insulation structure, 11-crucible support plate, 12-diversion gas homogenizing plate, 13-lower side heater, 14-nozzle heater, 15-nozzle, 16-inner heat insulation structure, 17-coating film detection unit, 18-vacuum cavity and 19-substrate.

Detailed Description

The following detailed description of preferred embodiments of the invention is made in connection with the accompanying drawings, which form a part hereof, and together with the description of the embodiments of the invention, are used to explain the principles of the invention and are not intended to limit the scope of the invention.

In a specific embodiment of the present invention, as shown in fig. 1-16, a linear evaporation source for evaporating downward is disclosed, which comprises a supporting structure 9, an outer crucible 7 and a material crucible 6, wherein the supporting structure 9, the outer crucible 7 and the material crucible 6 are sequentially sleeved from outside to inside, the upper end of the outer crucible 7 is connected with an outer crucible cover plate 4 in a sealing manner, a crucible supporting plate 11 and at least one porous flow guiding gas homogenizing plate 12 are arranged in the outer crucible 7 from top to bottom, the material crucible 6 is placed on the crucible supporting plate 11, a heater is arranged between the outer crucible 7 and the supporting structure 9, a plurality of nozzles 15 for spraying vapor to a base material 19 are arranged at the lower end of the outer crucible 7, and an opening structure for extending out the nozzles 15 is arranged at the bottom of the supporting structure 9.

Compared with the prior art, the linear evaporation source can realize downward evaporation coating, when materials are heated in the material crucible 6 to generate steam, the steam cannot be discharged from the upper part of the outer crucible 7 because the outer crucible 7 is of a sealed structure, and because the lower end of the outer crucible 7 is provided with the plurality of nozzles 15, the steam can be discharged through the nozzles 15 after passing through the diversion gas homogenizing plate 12, and the diversion gas homogenizing plate 12 is provided with the plurality of holes, so that the steam can be discharged through the nozzles 15 more uniformly to carry out coating, and the materials in the coating can be more uniform.

Specifically, the evaporation source of the present invention is used in a vacuum environment, and the evaporation source and the base material 19 are both contained in the vacuum chamber 18.

In a specific embodiment, the crucible supporting plate 11 and the diversion and air homogenizing plate 12 are movably connected with the outer crucible 7. Illustratively, as shown in fig. 15 and 16, a plurality of bosses are provided inside the outer crucible 7, and the crucible supporting plate 11 and the flow-guiding gas-homogenizing plate 12 are placed on the bosses.

The number of the diversion and uniform gas plates 12 can be selected according to the practical situation, so long as the steam can be uniformly distributed, the steam can be discharged through the nozzle 15 to meet the coating process requirement, the diversion and uniform gas plates 12 are movably connected with the outer crucible 7, and the diversion and uniform gas plates 12 can be conveniently disassembled and assembled. Wherein, the holes on the diversion and air homogenizing plate 12 can be uniformly arranged or non-uniformly arranged, and the shapes of the holes can be various shapes such as round, square and the like. As shown in fig. 13, the holes of the flow-guiding and homogenizing plate 12 of the present invention are uniformly arranged.

When the structures of the crucible supporting plate 11 and the diversion air homogenizing plate 12 are the same or different, the crucible supporting plate 11 is provided with a plurality of holes, and the position where the material contacts with the crucible supporting plate 11 is not provided with holes, as shown in fig. 14.

In one embodiment, the inner diameter of the outer crucible 7 is the same or gradually decreases from top to bottom, and the inner diameter of the outer crucible 7 gradually decreases from top to bottom.

Illustratively, as shown in fig. 15, the inner diameter and the outer diameter of the outer crucible 7 are simultaneously reduced from top to bottom, or as shown in fig. 16, the inner diameter of the outer crucible 7 is gradually reduced from top to bottom, and the outer diameter is unchanged from top to bottom.

Specifically, when the inner diameter of the outer crucible 7 gradually decreases from top to bottom, and the effect of step-by-step gas homogenization is realized by matching with a plurality of flow-guiding gas homogenizing plates 12, steam can be sprayed onto the base material 19 from top to bottom through the nozzle 15, and the uniformity of the evaporating material is better.

The supporting structure 9 in the invention plays a role in fixing and supporting the stress of the evaporation source integral structure.

In one embodiment, the material crucible 6 is provided with one or more.

Specifically, the material crucible 6 may be a single row single crucible, a single row multiple crucibles, a plurality of rows single crucibles (one crucible for each row) or a plurality of rows multiple crucibles (a plurality of crucibles for each row), as shown in fig. 5, and the present invention is illustrated by taking 3 rows as an example.

In a specific embodiment, a material crucible diversion cover plate 5 is disposed at the upper end of the material crucible 6, and a plurality of diversion holes are disposed on the material crucible diversion cover plate 5.

Specifically, the diversion holes can be uniformly arranged or non-uniformly arranged, and can be in various shapes such as round, square and the like, and the invention is not particularly limited and is within the protection scope of the invention. The material crucible diversion cover plate 5 plays a role in preliminary gas homogenization, and the uniformity of steam in the outer crucible 7 is increased after the steam evaporated from the material crucible 6 passes through the diversion holes.

In one embodiment, the heater includes an upper side heater 8 and/or a lower side heater 13 disposed in a vertical direction.

In a preferred embodiment, the heater further comprises an upper heater 3 provided on the support structure cover plate 2 or the outer crucible cover plate 4.

In a preferred embodiment, the heater further comprises a nozzle heater 14 provided inside (as shown in fig. 11) or outside (as shown in fig. 12) the bottom of the outer crucible 7.

The upper heater 8 is located at the upper part of the outer crucible 7, and the height direction covers the position of the material crucible 6 in the height direction, and heats the material crucible and the inner material by heating and diathermy of the outer crucible 7, and the evaporation material is evaporated and stably maintained in cooperation with the upper heater 3 or mainly using one heater or only using one heater. According to the process requirements, the coating width direction (perpendicular to the movement direction of the base material 19) is divided into a single temperature zone or a plurality of temperature zones for heating, and the number of the temperature zones is controlled to meet the coating width and the process requirements.

The lower heater 13 is located at the lower part of the outer crucible 7, covers the outer lower part of the outer crucible 7, passes through the inner heat insulation structure 16 until the nozzle 15 is located, and maintains the temperature of the evaporation material gas flowing downwards in the outer crucible 7 or to the process required temperature through heating by various heaters and diathermy of the outer crucible 7, so that the whole process meets the process requirements, and the nozzle 15 does not deposit evaporation material and is not blocked. According to the process requirements, the coating width direction (perpendicular to the movement direction of the substrate 19) can be divided into single-temperature zones or multi-temperature zones for heating, and the number and control requirements of the temperature zones are based on the width of the coating zone and the process requirements.

The upper heater 3 is located on the outer crucible cover 4, heats the outer crucible cover 4 and is transparent to the material crucible 6, and the evaporating material is evaporated and stably maintained in cooperation with the upper side heater 8 or mainly using one heater or only using one heater. The heating device can be divided into a single temperature zone or a plurality of temperature zones for heating along the width direction of the coating (perpendicular to the moving direction of the substrate 19) according to the process requirements, and the number and the control requirements of the temperature zones are based on the width of the coating zone and the process requirements. Depending on the material, heating temperature and structural design, it may be mounted to the support structure cover plate 2 or to the outer crucible cover plate 4 depending on the structure and design.

The nozzle heater 14 controls the temperature of the nozzle 15 to meet the requirements of the process and coating film by heating the auxiliary lower side heater 13, and ensures that the nozzle 15 is unobstructed and no evaporation material is deposited in the whole process. The nozzle heater 14 can be divided into a single temperature zone or a plurality of temperature zones for heating along the width direction of the coating (perpendicular to the moving direction of the substrate 19) according to the process requirements, and the number and the control requirements of the temperature zones are according to the width of the coating and the process requirements.

Specifically, the upper heater 3, the upper side heater 8, the lower side heater 13, and the nozzle heater 14 are identical or different in shape. By way of example, one of a spiral (fig. 7), S-type (fig. 8), n-type (fig. 9) or annular n-type (fig. 10) configuration may be employed. The shape of the heater in the invention is not limited to the above shape, and a person skilled in the art can divide the heater into a plurality of sections according to the heating design to form multi-temperature-zone heating so as to meet the heating temperature field requirement. The heater of the present invention adopts resistance heating.

The evaporation source provided by the invention performs multistage gas homogenization through the gas homogenization guide plate, and is combined by four optional heaters, and the process requirements such as uniformity and the like are more easily met through the adaptation of the gas homogenization layer number and the heaters. And the method can be widely applied from low temperature to about 1500 ℃, is not only suitable for medium and low temperature materials such as organic matters and the like, but also used for metal materials such as silver, copper, aluminum and the like, and has much wider applicability for evaporation materials compared with other evaporation technologies.

In one embodiment, as shown in FIG. 6, the nozzle 15 is angled at an angle α from the horizontal, where 0 ° < α+.ltoreq.90°. The angle between the nozzle 15 and the horizontal direction can be adjusted according to the actual requirements.

Specifically, the nozzles 15 may be arranged in one or more rows, such as two rows in fig. 5 and one row in fig. 6, and the nozzles 15 and the outer crucible 7 are integrally formed according to actual process requirements, or may be assembled separately, and each nozzle 15 is hermetically connected with the bottoms of the outer crucible 7 and the support structure 9, so that steam is sprayed onto the substrate 19 through the nozzles 15.

In one embodiment, the support structure 9 is sleeved inside the heat insulation device.

Specifically, the heat insulation device is composed of an upper heat insulation structure 1 and side and lower heat insulation structures 10. The heat insulation device is used for integrally insulating the heat shield of the evaporation source. The insulating means may be one or more layers.

Specifically, after the material is filled in the material crucible 6, the upper heat insulation structure 1 covers the side and lower heat insulation structures 10 for heat insulation of the whole structure, and the number of layers and the side and lower heat insulation structures 10 assist in maintaining a heating environment temperature field to meet the process requirements according to the temperature and the process requirements. The side part and the lower part heat insulation structure are arranged around and below the supporting structure 9, the heat insulation device can be provided with a plurality of layers, and the number of layers is according to the temperature and the technological requirements. The material of the specific heat insulation device can be selected from heat insulation materials such as a metal material reflecting screen or a graphite felt, or the heat insulation materials such as the metal material reflecting screen and the graphite felt are combined. Except the air outlet position of the nozzle 15, other structures such as the heater, the outer crucible 7, the outer crucible cover plate 4 and the like are all coated inside the heat insulation device, so that a temperature field structure formed by a plurality of heaters meets the process requirements, meets the requirements on precision, uniformity and repeatability of temperature control and film coating, reduces power loss and improves useful power under the condition of meeting the requirements on equipment production, maintenance and the like.

In one embodiment, an inner insulating structure 16 is provided between the upper side heater 8 and the lower side heater 13. The inner heat insulation structure 16 is used for heat insulation barriers of the upper side heater 8 and the lower side heater 13, plays a role of spacing temperature fields, and the inner heat insulation structure 16 can be provided with a plurality of layers according to process requirements. The heat insulation device and all the heater designs ensure that the temperature field inside the linear evaporation source meets the material and process requirements, and meanwhile, the proportion of useful power is improved, the use function is achieved, and meanwhile, the production energy cost is reduced.

In a specific embodiment, the linear evaporation source is further electrically connected to a plating film detection unit 17.

Specifically, the film plating detection unit 17 belongs to the prior art, is an optional standard component, performs matching selection according to the film plating process requirement, acquires data such as real-time film plating rate, evaporation rate, film thickness uniformity and the like, feeds back the data, controls the heating and film plating process of the heater through a program or a PLC, and can adopt automatic control or manual control in the film plating process.

The substrate 19 of the present invention may be a flat substrate or a flexible substrate. The materials of the parts are selected according to the evaporating temperature, and the materials of the heater and other parts at the temperature below 700-800 ℃ basically have higher proportion of metal materials, and the materials with higher heating temperature and more proportion of high-temperature materials such as ceramics, graphite, tungsten, molybdenum, tantalum, niobium refractory metals and the like are applied.

The invention can be selectively described by the following parts: the different specific material characteristics such as the temperature, melting or sublimating, molecular weight and the like of the evaporating material can cause a plurality of variables such as the application or non-application of optional parts, material selection, heater segmentation, heater shape, heat insulation material layer number, flow guide hole parameters, flow guide plate series, nozzle 15 parameters and the like when stable evaporating film coating is realized, and the principle is unchanged.

The linear evaporation source can meet the requirement of linear evaporation of organic or inorganic materials below 700-800 ℃ downwards or obliquely downwards, and can also be a linear evaporation source structure for linear evaporation of metal materials such as copper, aluminum, silver and the like in a temperature range from 700-800 ℃ to about 1500 ℃, and the width of a coating film is not limited in principle.

The invention realizes the linear evaporation source for downwards coating, can solve the requirement of hope of evaporation technology for downwards evaporation due to wider and wider mass production width in the industries of photovoltaics and the like, has better uniformity of evaporation materials, meets the technological requirement of coating, and can realize downwards evaporation coating from low temperature to about 1500 ℃ in a wide temperature range. When the temperature range is lower than 700-800 ℃, an armored heater is used for heating and evaporating, and the inside is basically of a metal structure, so that the evaporation of medium-low temperature organic materials and compounds used in the photovoltaic direction industry such as perovskite and the like can be satisfied. If the process temperature is higher and higher, even approaches 1500 ℃, the proportion of high temperature such as ceramics, graphite, tungsten, molybdenum, tantalum, niobium and the like used as a heater or a high temperature area material is gradually increased, so that metal materials such as copper, aluminum, silver and the like can be evaporated. The invention solves the technical problems of downward coating mode and structure, the coating width can be increased according to the process requirement or the technical iteration requirement and is not limited, thereby meeting the problems of higher and higher productivity, unit cost and equipment cost performance.

The use process of the linear evaporation source of the invention is as follows:

(1) Opening the upper heat insulation structure 1 and the support structure cover plate 2, and then opening the outer crucible cover plate 4 to maintain the inside of the linear evaporation source;

(2) After maintenance is finished, when the material is required to be loaded, the material crucible diversion cover plate 5 is opened, the material crucible 6 is cleaned and maintained, the evaporation coating material is added into the material crucible 6, and the integral structure of the evaporation source is reset after the material is added;

(3) The evaporation source works in a vacuum system, and after the set vacuum condition and interlocking condition are reached, the heating process is started, and according to the material and process requirements, the upper heater 3, the upper heater 8, the lower heater 13 and the nozzle heater 14 can evaporate and stably maintain the evaporation material meeting the process requirements by one or a combination of more than one of the upper heater, the upper heater 8, the lower heater 13 and the nozzle heater;

(4) The evaporated material vapor is primarily homogenized through the material crucible diversion cover plate 5 and the multiple-stage homogenization of the diversion homogenizing plates 12, and then is sprayed to the substrate 19 through the nozzle 15.

The technical scheme of the invention is further explained below by combining specific examples.

Example 1

As shown in fig. 1, the linear evaporation source for downward evaporation in this embodiment includes a supporting structure 9, an outer crucible 7 and a material crucible 6 which are sequentially sleeved from outside to inside, the upper end of the outer crucible 7 is hermetically connected with an outer crucible cover plate 4, a crucible supporting plate 11 and at least one flow guiding air homogenizing plate 12 with multiple holes are arranged in the outer crucible 7 from top to bottom, the material crucible 6 is placed on the crucible supporting plate 11, a heater is arranged between the outer crucible 7 and the supporting structure 9, a plurality of nozzles 15 for spraying vapor to a base material 19 are arranged at the lower end of the outer crucible 7, and an open pore structure for extending out of the nozzles 15 is arranged at the bottom of the supporting structure 9.

The evaporation source of this embodiment is used in a vacuum environment, and the evaporation source and the base material 19 are both contained in the vacuum chamber 18. The number of the flow-guiding and homogenizing plates 12 in this embodiment is illustrated by taking 3 as an example. Each flow-guiding gas-homogenizing plate 12 and each crucible supporting plate 11 are movably connected with the outer crucible 7, for example, a boss is arranged in the outer crucible 7, and the flow-guiding gas-homogenizing plates 12 and the crucible supporting plates 11 are placed on the boss. The inner diameter of the outer crucible 7 of this embodiment is the same from top to bottom.

The crucible support plate 11 of this embodiment is different from the flow guiding and homogenizing plate 12 in structure, and the crucible support plate 11 is provided with a plurality of holes, and the position where the material contacts the crucible support plate 11 is not provided with holes, as shown in fig. 14.

The material crucible 6 of this embodiment is provided with a row of three, totally sets up 3 material crucible 6, material crucible 6 upper end be provided with material crucible water conservancy diversion apron 5, material crucible water conservancy diversion apron 5 on be provided with a plurality of water conservancy diversion holes.

Specifically, the heater includes an upper heater 8 and a lower heater 13 disposed in a vertical direction, an upper heater 3 disposed on the support structure cover plate 2, and a nozzle heater 14 disposed inside the bottom of the outer crucible 7. The angle between the nozzle 15 and the horizontal direction in this embodiment is 90 °, as shown in fig. 4.

The support structure 9 of this embodiment is sleeved inside a heat insulation device, which consists of an upper heat insulation structure 1 and side and lower heat insulation structures 10. An inner heat insulation structure 16 is arranged between the upper side heater 8 and the lower side heater 13.

The evaporation source of the embodiment is also electrically connected with a film coating detection unit 17, the data detected by the film coating detection unit 17 is fed back to the control system, and the power output of the heater is controlled to meet the evaporation rate and film thickness uniformity of materials and the film coating process in the photovoltaic field.

Example 2

The evaporation source of this embodiment is the same as that of embodiment 1 except that the nozzles 15 are disposed obliquely downward as shown in fig. 6.

Example 3

The evaporation source of this example is the same as that of example 1, except that the inner diameter and the outer diameter of the outer crucible 7 are gradually reduced from top to bottom as shown in fig. 15, forming a "pitch-height" structure.

Example 4

The evaporation source of this example is the same as that of example 3, except that the inner diameter of the outer crucible 7 gradually decreases from top to bottom and the outer diameter is the same from top to bottom as shown in fig. 16, and the inside of the outer crucible 7 has a "pitch-height" structure.

The present invention is not limited to the above-mentioned embodiments, and any changes or substitutions that can be easily understood by those skilled in the art within the technical scope of the present invention are intended to be included in the scope of the present invention.

Claims

1. The linear evaporation source is characterized by comprising a supporting structure, an outer crucible and a material crucible which are sleeved in sequence from outside to inside, wherein the upper end of the outer crucible is hermetically connected with an outer crucible cover plate, a crucible supporting plate and at least one porous flow guiding air homogenizing plate are arranged in the outer crucible from top to bottom, the material crucible is placed on the crucible supporting plate, a heater is arranged between the outer crucible and the supporting structure, a plurality of nozzles for spraying steam to a base material are arranged at the lower end of the outer crucible, and an opening structure for the nozzles to extend out is arranged at the bottom of the supporting structure;

One or more material crucibles are arranged, a material crucible diversion cover plate is arranged at the upper end of the material crucible, and a plurality of diversion holes are formed in the material crucible diversion cover plate; the crucible supporting plate is provided with a plurality of holes;

The heater comprises an upper side heater and a lower side heater which are arranged in the vertical direction, an upper heater arranged on the cover plate of the supporting structure or the cover plate of the outer crucible, and a nozzle heater arranged on the inner side or the outer side of the bottom of the outer crucible; an inner heat insulation structure is arranged between the upper side heater and the lower side heater, the upper side heater is positioned at the outer upper part of the outer crucible, the height direction covers the position of the crucible in the height direction, the lower side heater is positioned at the lower part of the outer crucible, and the lower part of the outer crucible is covered by the inner heat insulation structure until reaching the position of the nozzle;

the heating temperature of the linear evaporation source is less than or equal to 1500 ℃.

2. The linear evaporation source according to claim 1, wherein the crucible supporting plate and the flow-guiding gas-homogenizing plate are movably connected with the outer crucible.

3. The linear evaporation source according to claim 1, wherein the inner diameter of said outer crucible is the same or gradually decreases from top to bottom.

4. The linear evaporation source according to claim 1, wherein said upper heater, upper side heater, lower side heater and nozzle heater are identical or different in shape.

5. The linear evaporation source according to any one of claims 1 to 4, wherein said nozzle has an angle α with respect to the horizontal, wherein 0 ° < α+.ltoreq.90°.

6. The linear evaporation source according to claim 5, wherein the nozzles are arranged in one or more rows.

7. The linear evaporation source according to any one of claims 1 to 4, wherein said support structure is arranged inside the heat insulating means.

8. The linear evaporation source according to claim 7, wherein said heat insulating means comprises an upper heat insulating structure and side and lower heat insulating structures.

9. The linear evaporation source for downward evaporation according to any one of claims 1 to 4, further comprising a plating film detecting unit electrically connected to said linear evaporation source.