Coating method and device for electronic information and optoelectronic materials

Abstract

The present invention provides an electronic information and optoelectronic material coating device for applying liquid optoelectronic material to a substrate, characterized in that the device comprises: a fluid conduit; an extrusion die connected to the fluid conduit for extruding optoelectronic material onto the substrate; a chuck for holding the substrate in a selected position relative to the extrusion die; a liquid pump connected to the fluid conduit; an intermediate reservoir connected to the fluid conduit for supplying liquid optoelectronic material to the liquid pump and the extrusion die; a heating unit connected to at least one of the intermediate reservoir, the fluid conduit, the chuck or the extrusion die for maintaining the optoelectronic material at a set temperature before or during or both the extrusion of the optoelectronic material onto the substrate; and a control system connected to at least the chuck and the extrusion die for directing and controlling the relative motion between the extrusion die and the chuck and for controlling the rate of extrusion of the optoelectronic material from the die.

Description

TECHNICAL FIELD

[0001] The present invention discloses a method and apparatus for the formation of a photovoltaic cell or structure for the conversion of light energy into electrical energy. BACKGROUND

[0002] Solar photovoltaic panels are devices that directly convert light into electricity at the atomic level. Certain materials have the property of the photoelectric effect, which enables them to absorb photons and release electrons, which are captured and made to flow in a directed manner to produce an electric current.

[0003] Structures containing materials with photovoltaic properties are commonly referred to as photovoltaic cells or more generally as solar cells. Solar cells are typically fabricated from silicon, the same semiconductor material used in the microelectronics industry. For such cells, a thin semiconductor wafer of silicon is specially treated and doped to form an electric field across the wafer, one side being positive and the other side being negative. When light strikes the solar cell, the atoms in the semiconductor material absorb light energy and release electrons. If wires are attached from the positive to the negative side, a flow of current results. This current can be used to power a load such as a light or a tool.

[0004] Many photovoltaic cells are electrically connected together and mounted in a support structure or frame, and are referred to as photovoltaic modules. Modules are designed to produce a certain voltage to power a load, such as the 12 volt system commonly used. The current produced is directly dependent on the amount of light.

[0005] As mentioned above, many photovoltaic cells are fabricated using semiconductor processing techniques to form photodiodes or other microelectronic structures on doped silicon or gallium arsenide wafers. Such processes include photolithography, ion implantation, etc. These processing techniques are costly and delicate, making the photovoltaic cells or structures expensive.

[0006] In addition to semiconductor type processing techniques, there are other methods of fabricating photovoltaic cells. A recent development in this field is the use of fluid photovoltaic materials. These materials have the physical properties of conventionally fabricated doped silicon semiconductors, but are available in fluid form. These fluid materials can be precisely applied to a variety of forms of substrates, such as glass sheets, metal foils, to form useful photovoltaic cells. SUMMARY

[0007] It is an object of the present invention to overcome the deficiencies of the prior art and to provide a method and apparatus for the application of photovoltaic fluid materials to fabricate photovoltaic cells.

[0008] In the present invention, the photovoltaic material refers to fluid photovoltaic materials.

[0009] The technical solution of the present invention is as follows:

[0010] An apparatus for coating electronic information and optoelectronic materials onto a substrate, said apparatus comprising:

[0011] a fluid conduit;

[0012] an extrusion die connected to the fluid conduit for extruding the optoelectronic material onto the substrate;

[0013] a chuck for holding the substrate in a selected position relative to the extrusion die;

[0014] a liquid pump connected to the fluid conduit;

[0015] an intermediate reservoir connected to the fluid conduit for supplying the liquid optoelectronic material to the liquid pump and the extrusion die;

[0016] a heating unit connected to at least one of the intermediate reservoir, the fluid conduit, the chuck, or the extrusion die for maintaining the optoelectronic material at a selected temperature prior to, during, or both prior to and during extrusion of the optoelectronic material onto the substrate;

[0017] a control system connected to at least the chuck and the extrusion die for directing and controlling the relative motion between the extrusion die and the chuck and for controlling the rate of extrusion of the optoelectronic material from the die.

[0018] said apparatus further comprising a gas suction device positioned adjacent to the substrate for removing gases emitted by the extruded optoelectronic material.

[0019] said apparatus further comprising:

[0020] a second intermediate reservoir;

[0021] a second liquid pump in communication with the second intermediate reservoir; said second liquid pump being in communication with the second intermediate reservoir;

[0022] a stirrer positioned in the fluid conduit for stirring the multi-component optoelectronic material from the reservoir prior to extrusion.

[0023] said gas suction device further comprising:

[0024] a plurality of vacuum ports formed in the chuck around the periphery of the substrate;

[0025] a vacuum source in communication with the vacuum ports.

[0026] said heating unit further comprising at least a resistive heating unit connected to at least one of the intermediate reservoir, the fluid conduit, the chuck, or the extrusion die.

[0027] said apparatus for coating electronic information and optoelectronic materials onto a substrate, comprising:

[0028] a base for the control system for the extrusion die and the chuck;

[0029] a platform and a slide assembly disposed on the base, a chuck disposed on the platform; the slide assembly is configured to carry an extrusion die, one or more intermediate reservoirs and a liquid pump, the chuck is configured to carry a substrate;

[0030] an extrusion die connected to a lower portion of the slide assembly, one or more intermediate reservoirs and a liquid pump connected to an upper portion of the slide assembly; the liquid pump and the intermediate reservoirs are in fluid communication with each other and with the extrusion die via fluid conduits; the fluid conduits between the intermediate reservoirs, the liquid pump and the extrusion die are provided with stirring units;

[0031] the device further comprises a heating unit, the heating unit is a hot plate stirrer assembly connected to the intermediate reservoirs, the hot plate stirrer assembly comprises a resistance cartridge heater and an electric coil assembly;

[0032] the chuck comprises a central portion and a plenum shroud, the plenum shroud surrounds and is fixed to the central portion;

[0033] the device further comprises a suction device, the suction device comprises a plurality of vacuum ports disposed on the chuck, and a vacuum source in communication with the vacuum ports.

[0034] a coating method of the photoelectric material coating device, comprising the following steps:

[0035] 1) fixing a substrate to the chuck;

[0036] 2) heating the photoelectric material at a set temperature and maintaining the set temperature;

[0037] 3) causing the heated liquid to be extruded from the intermediate reservoirs to the substrate at a controlled speed via the fluid conduits through the extrusion die;

[0038] 4) initiating a controlled relative motion between the extrusion die and the substrate, thereby depositing the photoelectric material on the substrate and expelling the organic gas volatilized from the photoelectric material.

[0039] the intermediate reservoirs storing the photovoltaic liquid are heated.

[0040] the fluid conduits communicating the photovoltaic liquid are heated.

[0041] the chuck is heated.

[0042] the extrusion die is heated.

[0043] The foregoing has outlined rather broadly the features and technical advantages of the present application so as to provide an overall understanding of the application's more complete description that follows. Additional features and advantages of the application will be described hereinafter that form the subject of the claims of the application. For a better appreciation of the application, reference should be made to the drawings wherein there are shown preferred embodiments of the application from the follow description and in which: BRIEF DESCRIPTION OF DRAWINGS

[0044] For a more complete understanding of the application, therefore, reference is now made to the following examples, taken in conjunction with the accompanying drawings in which:

[0045] Figure 1 is a perspective view of the apparatus of the illustrative embodiment of the application.

[0046] Figure 2 is a perspective view of the apparatus of the illustrative embodiment of the application. Figure 1 is an enlarged view of a portion of the apparatus.

[0047] Figure 3 is an enlarged view of a portion of the apparatus, particularly the heated reservoir of the application. Figure 2

[0048] Figure 4 is an enlarged view of a portion of the apparatus, particularly the heated extrusion die of the application. Figure 1

[0049] Figure 5 is an enlarged view of a portion of the apparatus, particularly the chuck of the application. Figure 2

[0050] wherein 11 is a coater, 13 is a base, 15 is a platform, 17 is a chuck or substrate holder, 19 is a slide assembly, 21 is a control system, 101 is an extrusion die, 103, 107 are intermediate reservoirs, 105 is a liquid pump, 109 is a hot plate stirrer assembly, 111 is a resistance cartridge heater, 113 is a stirring unit, 201 is a fluid manifold assembly, 301 is a central portion, 303 is a plenum. DETAILED DESCRIPTION

[0051] Reference will now be made to the drawings wherein like numerals refer to like parts throughout the several figures, and wherein: Figure 1 ​​​An apparatus for extruding or depositing liquid electronic and optoelectronic materials is described. The apparatus 11 is commonly referred to as an extruder or coater. According to the illustrative embodiment, the coater 11 includes a base 13 on which is mounted a platform 15 and a carriage assembly 19, a chuck or substrate holder 17 is mounted on the platform 15, and the carriage assembly 19 is mounted on a linear bearing system and is driven by a controlled servo or stepper motor according to the illustrated embodiment, which precisely controls the relative motion of the carriage assembly 19 with respect to the base 15 and the chuck 17. A computer-based control system controls the coating motion and other aspects of the system to adjust the deposition of the fluid on the substrate. The details are described below.

[0052] As will be described, precise control of the relative motion between the extrusion die (carried by the carriage assembly 19) and the substrate (carried by the chuck 17), in combination with the controlled flow rate of the fluid from the extrusion die, results in the controlled extrusion or deposition of the process fluid on the substrate, causing uniform application of a selected thickness of the coating on the substrate. Alternatively, the chuck 17 can be moved relative to the extrusion die and gantry, but such relative motion of the chuck 17 with respect to the substrate size range requires a large amount of space.

[0053] Figure 2 is Figure 1 An enlarged view of a portion of the carriage assembly 19 with the shroud removed, the extrusion die 101 is mounted on the lower portion of the carriage assembly 19, and the intermediate reservoir 103 and fluid pump 105 are mounted on the upper portion of the carriage assembly 19 and are in fluid communication with the extrusion die 101. For some applications, two or more components of the process fluid are used, and a second (or corresponding number) of intermediate reservoirs 107 and fluid pumps 105 are also carried by the carriage assembly 19. Each of the intermediate reservoirs 103, 107 is in fluid communication with a main reservoir of the process fluid (not shown), which is typically a process fluid container provided by the manufacturer and is specific to the particular fluid.

[0054] If a multi-component optoelectronic material is used, multiple reservoirs and fluid pumps are necessary to mix the components prior to deposition of the material on the substrate. Static mixing devices can be provided in the fluid conduits between the intermediate reservoirs 103, 107 and the fluid pump assembly 105 and the extrusion die 101, or dynamic mixing devices such as the magnetic stirrers or mixers described below can be used.

[0055] The liquid pump 105 and the intermediate reservoir 103 are in fluid communication with each other and with the extrusion die, so that the process fluid in the intermediate reservoir 103 is pressurized or forced to reach and pass through the extrusion die 101 to be dispensed or deposited (also known as extruded) on the substrate at a fine controlled rate. The liquid pump 105 is driven by a controllable motor such as a stepper motor or a servo motor, and the fluid dispensing is achieved by controlled actuation of the extrusion die 101 and of the pumping unit, such motor and related sensors (position sensor, limit switches, etc.) being connected to the control system 21.

[0056] Figure 3 The intermediate reservoir 103 and the liquid pump 105 assembly are shown in more detail, the intermediate reservoir 103 being mounted on a hot plate stirrer assembly 109, which comprises a pair of resistive cartridge heaters 111 and an electric coil assembly (not shown in the figures), the coil generating a magnetic field acting on a stirring unit 113 inside the intermediate reservoir. Thus, the hot plate stirrer assembly 109 heats and stirs or agitates the photovoltaic fluid of a certain viscosity in the intermediate reservoir 103, maintaining the fluid in a suitable condition (temperature and solid dispersion) suitable for extrusion or deposition, as described above, the conditioned fluid being fed from the intermediate reservoir 103 to the liquid pump 105, the photovoltaic fluid being pumped to the extrusion die under metered control.

[0057] According to the present application, Figure 4 The heated extrusion die 101 is shown, the photovoltaic fluid entering the extrusion die 101 through a fluid manifold assembly 201, which is connected to the control system 21 for process control, by heating and stirring the intermediate reservoir 103, as described above, the conditioning. The photovoltaic fluid flows at a controllable rate through the extrusion die 101, being extruded through an extrusion nozzle 203 to be deposited on the substrate. A plurality of cartridge resistive heaters are placed inside the extrusion die 101, maintaining the temperature required by the photovoltaic fluid until it is extruded from the die to be deposited.

[0058] According to the present application, Figure 5 The chuck 17 is shown, the chuck 17 comprising a flat central portion 301, which is the portion of the assembly to which the substrate (typically a thin glass panel) is fixed by mechanical or vacuum means, a plenum 303 surrounding and rigidly fixed to the central portion, the central portion 301 and the plenum 303 being rigidly mounted to another piece of granite slab, in contrast, the coating machine 11 ensuring the stability of the substrate with respect to the slide assembly 19 and the extrusion die 101.

[0059] Like the extrusion die 101 and the intermediate reservoir 103, the central portion 301 of the substrate or thin glass sheet is preferentially heated by placing a plurality of cylindrical heaters in the holes of the central portion 301 in a position calculated to at least uniformly heat the upper surface of the central portion 301 in contact with the substrate. Like the other heating elements, the cylindrical heaters are coupled to the control system 21 to control and maintain the temperature of the heating elements and, in turn, the temperature of the upper surface of the central portion 301 of the chuck. In some applications, it can be desirable to maintain the chuck and the substrate at the same temperature as the deposited fluid in order to maintain the flow characteristics of the fluid. In other applications, it can be desirable to maintain the chuck and the substrate at different temperatures in order to promote the formation of crystals or other material transformations in the deposited fluid as a thin film is formed on the substrate.

[0060] A plurality of vacuum ports are provided around the periphery of the central portion 301 and a plenum 303 is coupled to a vacuum or suction source (not shown) that provides sufficient vacuum to remove a substantial amount of toxic or hazardous gases emitted from the photovoltaic fluid after deposition of the photovoltaic material. Although the coater is typically operated in a clean environment, the clean room environment can be controlled to minimize particulate contaminants, but not gases or vapors, many photovoltaic fluids emit or release toxic or hazardous vapors and, therefore, a vacuum or other means of removing these fluids should be provided after deposition. The upper portion of the coater 11 including the slide assembly 19 and the chuck 17 can be enclosed with a hood or similar exhaust structure to exclude toxic or hazardous vapors.

[0061] In operation, typically a thin glass sheet substrate is secured to the chuck 17, the fluid pump begins to supply the photovoltaic fluid to the intermediate reservoir 103 and heats or maintains a desired process temperature, the magnetic stirrer (or other stirrer) maintains the photovoltaic fluid in a mixed state so that there is sufficient dispersion of solids in the fluid, the fluid pump 105 delivers a precise amount of photovoltaic fluid at a controlled rate to the extrusion die 101, and the desired process temperature is maintained by the heating elements in the die as the photovoltaic fluid is extruded from the extrusion die 101 and deposited or dispensed, and the controlled relative motion between the slide assembly 19 and the chuck 17 is initiated so that the photovoltaic fluid is dispensed onto the substrate in a manner that forms a thin film of uniform thickness.

[0062] The application has been described with reference to certain preferred embodiments thereof, it being understood that the embodiments disclosed are illustrative in nature and not limiting, and that numerous modifications, variations and alternatives are possible within the foregoing disclosure. In some instances, some features of the application can be used without the corresponding use of other features. Accordingly, the appended claims as interpreted in their broadest reasonable manner are apt to be construed in a manner consistent with the scope of the application as disclosed herein.

Claims

1. An electronic information and optoelectronic material coating apparatus, used to apply liquid optoelectronic materials to a substrate, characterized in that, The coating apparatus includes: Fluid conduit; An extrusion die connected to a fluid conduit is used to extrude optoelectronic materials onto a substrate; A chuck for fixing the substrate in a selected position relative to the extrusion die; A liquid pump connected to a fluid conduit; An intermediate reservoir connected to a fluid conduit is used to supply liquid optoelectronic materials to the liquid pump and the extrusion die; A heating unit connected to at least one of the intermediate liquid reservoir, fluid conduit, chuck, or extrusion die is used to maintain the optoelectronic material at a set temperature before, during, or both of the extrusion of the optoelectronic material onto the substrate. A control system, which is at least connected to the chuck and the extrusion die, is used to guide and control the relative movement between the extrusion die and the chuck, and to control the extrusion speed of the optoelectronic material from the die; The coating apparatus further includes: Base; control system for controlling the extrusion die and the chuck; A platform and a slide assembly are provided on a base, and a chuck is provided on the platform; the slide assembly is used to support the extrusion die, one or more of the intermediate liquid storage tanks and the liquid pump, and the chuck is used to support the substrate; The extrusion die is connected to the lower part of the slide assembly, and one or more intermediate liquid storage tanks and the liquid pump are connected to the upper part of the slide assembly; the liquid pump and the intermediate liquid storage tanks are connected to each other and to the extrusion die through a fluid conduit; a stirring unit is provided in the fluid conduit between the intermediate liquid storage tanks, the liquid pump and the extrusion die; The coating apparatus further includes the heating unit, which is a hot plate agitator assembly connected to the intermediate liquid storage tank. The hot plate agitator assembly includes a resistance cylinder heater and an electric coil assembly. The chuck includes a central portion and a pressure shield, the pressure shield surrounding and fixed to the central portion; The coating apparatus further includes a suction device, which includes multiple vacuum ports on a chuck and a vacuum source connected to the vacuum ports.

2. The electronic information and optoelectronic material coating apparatus according to claim 1, characterized in that, The suction device is located near the substrate and is used to remove the gas emitted by the extruded optoelectronic material.

3. The electronic information and optoelectronic material coating apparatus according to claim 1, characterized in that, The coating apparatus further includes: Second intermediate storage tank; A second liquid pump connected to a second intermediate liquid storage tank; the second liquid pump is connected to the second intermediate liquid storage tank; A stirrer installed in a fluid conduit is used to stir multi-component optoelectronic materials from a storage tank before extrusion.

4. The electronic information and optoelectronic material coating apparatus according to claim 2, characterized in that, The suction device further includes: Numerous vacuum ports are formed around the periphery of the substrate and within the chuck; A vacuum source connected to a vacuum port.

5. The electronic information and optoelectronic material coating apparatus according to claim 1, characterized in that, The heating unit further includes at least one resistance heating unit connected to at least one of the intermediate liquid storage tank, fluid conveyor, chuck, or extrusion die.

6. The coating method of the electronic information and optoelectronic material coating apparatus as described in any one of claims 1-5, characterized in that, Includes the following steps: 1) Secure the substrate to the chuck; 2) Heat the photoelectric material at a set temperature and maintain the set temperature; 3) The heated liquid is extruded from the intermediate storage tank through the extrusion die and onto the substrate at a controlled speed via a fluid conduit; 4) It induces a controllable relative movement between the extrusion die and the substrate, thereby depositing optoelectronic materials on the substrate and expelling the volatile organic gases emitted by the optoelectronic materials.

7. The method according to claim 6, characterized in that, The intermediate storage tank for storing photovoltaic liquid is heated.

8. The method according to claim 6, characterized in that, The fluid conduit connecting the photovoltaic liquid is heated.

9. The method according to claim 6, characterized in that, The chuck is heated.

10. The method according to claim 6, characterized in that, The extrusion die is heated.

Images