KR101209878B1 - Phosphor coating device and Phosphor coating method - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a phosphor coating device and a coating method that can be easily handled to a phosphor material, prevent the phenomena of phosphors from being broken, and can be mass-produced due to a relatively simple manufacturing process.
More specifically, the present invention, the transfer means for transferring a plurality of semiconductor wafers at regular intervals; And coating means for coating phosphor on at least one surface of the semiconductor wafer, wherein the coating means includes a phosphor roll on which a photosensitive film including phosphor is formed in a roll shape. Provide a coating device.

Description

Phosphor coating device and Phosphor coating method

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a phosphor coating device and a coating method that can be easily handled to a phosphor material, prevent the phenomena of phosphors from being broken, and can be mass-produced due to a relatively simple manufacturing process.

Light emitting diodes (LEDs) are solid state devices that convert electrical energy into light and generally comprise an active layer of one or more semiconductor materials sandwiched between oppositely doped layers. When a bias is applied across these doped layers, holes and electrons are injected into this active layer where holes and electrons recombine to generate light.

Conventional LEDs cannot generate white light from their active layer. Light from blue light emitting LEDs is converted to white light by enclosing the LEDs with yellow phosphors, polymers or dyes, a typical phosphor being cerium doped yttrium aluminum garnet (Ce: YAG). .

The material of the phosphor surrounding the LED downconverts the wavelength of a portion of the blue light of the LED, thereby changing the color of the LED light to yellow. A part of the blue light passes through the phosphor without being changed, but a substantial part of the light is converted down to yellow. The LED emits blue light and yellow light, which combine to provide white light. In another approach, light from a purple or ultraviolet emitting LED is converted to white light by surrounding the LED with a multicolored phosphor or dye.

One conventional method for coating an LED with a phosphor layer uses a syringe or nozzle to inject a phosphor mixed with an epoxy resin or silicone polymer onto the LED. However, using this method, it is difficult to control the geometry and thickness of the phosphor layer.

As a result, light emitted from the LED at different angles can pass through different amounts of conversion material, which can result in an LED having a non-uniform color temperature as a function of viewing angle. Since it is difficult to control the geometry and thickness, it may also be difficult to consistently reproduce LEDs having the same or similar emission characteristics.

Another conventional method for coating LEDs is by stencil printing. A plurality of light emitting semiconductor elements are disposed on a substrate with a desired distance between adjacent LEDs. A stencil with openings aligned with the LED is provided, which are slightly larger than the LEDs and the stencil is thicker than the LED. The stencil is disposed on the substrate, and each of the LEDs is positioned within a respective opening of the stencil.

Next, a predetermined composition is deposited on the stencil openings to coat the LED, which is a phosphor of a silicone polymer that can be cured by heat or light. After these holes are filled, the stencil is removed from the substrate and the stencil composition cures to a solid state.

As with the above-described syringe method, it is also difficult to control the geometry and the layer thickness of the phosphor-containing polymer by using the stencil method. Stencil compositions may not fully fill the stencil openings, resulting in problems that the layers may not be uniform.

The phosphor containing composition may also be adhered to the stencil opening, which reduces the amount of composition remaining on the LED. The stencil opening may also not be aligned with the LED. These problems can cause the LED to have non-uniform color temperature and make it difficult to reproduce the LED consistently with the same or similar emission characteristics.

In addition, various LED coating methods have been developed, including spin coating, spray coating, electrostatic deposition (ESD) and electrophoretic deposition (EPD).

Processes such as spin coating or spray coating typically use binder material during phosphor deposition, but other processes require the addition of a binder immediately after deposition of the particles / powders of the phosphor to stabilize the particles / powders of the phosphor. .

In these approaches, the main challenge is to access the wire bond pads on the device after the coating process. Accessing wire bond pads with standard wafer fabrication techniques is difficult with conventional silicon binding materials as well as other binder materials such as epoxy or glass. Silicon has the problem of being incompatible with some developer as well as commonly used wafer fabrication materials such as acetone, and resist stripper.

This may limit the options and choices for a particular silicon or process step. Silicones also cure at high temperatures beyond the glass transition temperatures of commonly used photoresists. Thus, cured silicon films with phosphors are difficult to etch and have very low etch rates in chlorine and CF4 plasmas, and wet etching of cured silicon is typically inefficient.

Therefore, i) a method for easily forming a phosphor on a wafer regardless of the phosphor material, ii) a method for securing stability without breaking the phosphor, and iii) a phosphor coating capable of mass production in a relatively simple manufacturing process. There is a need for an apparatus and a coating method.

The present invention has been made to solve the above-mentioned problems of the prior art, and an object thereof is to provide a coating apparatus and a coating method which can easily form a phosphor on a semiconductor wafer regardless of the material of the phosphor.

In addition, another object of the present invention is to provide a coating apparatus and a coating method for forming a phosphor using a flexible phosphor material to prevent cracking of a phosphor formed on a semiconductor wafer to ensure stability of the phosphor.

In addition, the present invention has another object to enable the mass production of wafer-level phosphor with a simple manufacturing process and low manufacturing cost.

The technical objects to be achieved by the present invention are not limited to the above-mentioned technical problems, and other technical subjects which are not mentioned can be clearly understood by those skilled in the art from the description of the present invention .

According to an aspect of the present invention to solve the above problems of the prior art, a transport means for transporting a photosensitive film comprising a phosphor; At least one protective film roll passing through the photosensitive film including the phosphor to form a protective film on the upper or lower portion of the photosensitive film; It provides a phosphor roll manufacturing apparatus comprising a; and a first roll for producing the photosensitive film formed with the protective film in the form of a roll.

In addition, according to another aspect of the invention, the transfer means for transferring a plurality of semiconductor wafers at regular intervals; And coating means for coating phosphor on at least one surface of the semiconductor wafer, wherein the coating means includes a phosphor roll on which a photosensitive film including phosphor is formed in a roll shape. Provide a coating device.

In the present invention, the phosphor roll includes a phosphor coating device comprising a photosensitive film including a phosphor therein and a protective film deposited on upper and lower portions of the photosensitive film.

In the present invention, the photosensitive film includes a phosphor coating device, characterized in that formed using any one or more materials selected from polysiloxane, polyimide, polydimethylsiloxane, or acrylic resin. do.

In the present invention, the protective film includes a phosphor coating device, characterized in that formed using any one or more materials from polyethylene terephthalate (PET), polybutylene terephthalate (PBT) or polyester-based resin.

The thickness of the photosensitive film in the present invention includes a phosphor coating device, characterized in that 10um to 100um.

The thickness of the protective film in the present invention includes a phosphor coating device, characterized in that 100um to 500um.

In the present invention, the coating means includes a phosphor roll located on the upper surface or the lower surface of the transfer means and a pressing roll positioned on the opposite side of the phosphor roll to pressurize the photosensitive film containing the phosphor to be deposited on the semiconductor wafer. It includes a phosphor coating device characterized in that.

In the present invention, the conveying means comprises a phosphor coating device, characterized in that the conveyor belt including a conveying conveyor.

The present invention comprises the steps of forming a phosphor in or on the photosensitive film; Forming a protective film on the upper and lower portions of the photosensitive film by passing the photosensitive film including the phosphor through the protective film roll by a transfer unit; And forming a phosphor roll by passing the photosensitive film on which the protective film is formed to a first roll to form a phosphor roll.

In the present invention, the forming of the phosphor includes a method of manufacturing a phosphor roll, which includes applying a phosphor on a first photosensitive film and depositing a second photosensitive film on the phosphor.

In the present invention, the phosphor forming step and the protective film forming step, the step of coating and applying the phosphor and the photosensitive resin on the protective film, the step of curing the photosensitive resin in which the phosphor is blended and protect the protective film formed of the photosensitive resin It includes a method for producing a phosphor roll characterized in that the step of passing through the film roll to form a protective film on top of the photosensitive resin.

The present invention comprises the steps of transferring the at least one semiconductor wafer through the phosphor roll and the compression roll to apply a photosensitive film and a protective film comprising a phosphor, removing the protective film formed on the semiconductor wafer and on the semiconductor wafer It provides a phosphor coating method comprising the step of forming a wire bonding pad by removing a predetermined region of the photosensitive film comprising a phosphor formed on.

The present invention includes a phosphor coating method further comprising the step of irradiating ultraviolet light on the semiconductor wafer after the protective film removing step.

The wavelength band of the ultraviolet ray in the present invention includes a phosphor coating method, characterized in that 360nm to 405nm.

In the present invention, the wire bonding pad forming step includes a phosphor coating method for forming a wire bonding pad by using any one of a drill selected from a laser drill, a CO2 drill, or a yag drill.

According to the phosphor coating device and the coating method of the present invention, since the handling of the material of the phosphor is easy, there is an effect that the phosphor can be easily formed on the semiconductor wafer regardless of the material of the phosphor.

In addition, by forming the phosphor using the flexible phosphor material by the phosphor coating apparatus and the coating method of the present invention, there is an effect of preventing the phosphor cracking on the semiconductor wafer, and ensure the stability of the phosphor.

In addition, the phosphor coating apparatus and the coating method of the present invention has the effect of enabling the mass production of wafer-level phosphors with a simple manufacturing process and low manufacturing cost.

1 is an exemplary view illustrating a protective film deposited on upper and lower portions of a photosensitive film including a phosphor according to an embodiment of the present invention.
Figure 2a is an example of a phosphor roll manufacturing apparatus according to an embodiment of the present invention.
2b to 2d is an exemplary view showing a process of depositing a protective film on the upper and lower portions of the photosensitive film including the phosphor according to an embodiment of the present invention.
Figure 3a is an exemplary view of a phosphor coating device according to an embodiment of the present invention.
Figure 3b is a plan view of the phosphor coating device according to an embodiment of the present invention.
4A to 4C are exemplary views illustrating the formation of wire bonding pads on a semiconductor wafer according to an embodiment of the present invention.
Figure 5 is a flow chart of the phosphor roll manufacturing method according to an embodiment of the present invention.
6 is a flow chart of a phosphor coating method according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms, and the inventor should appropriately interpret the concepts of the terms appropriately It should be interpreted in accordance with the meaning and concept consistent with the technical idea of the present invention based on the principle that it can be defined. Therefore, the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention and do not represent all the technical ideas of the present invention. Therefore, It is to be understood that equivalents and modifications are possible.

1 is an exemplary view illustrating a protective film deposited on upper and lower portions of a photosensitive film including a phosphor according to an embodiment of the present invention.

The present invention provides a coating apparatus and a coating method for performing a phosphor coating process of the semiconductor wafer level, the upper surface or the lower surface of the semiconductor wafer, to compress the photosensitive film 102, the protective film 103 is deposited; do. The photosensitive film 102 including the phosphor 101 is manufactured in a roll form together with the protective film 103 to be pressed onto the wafer.

Referring to FIG. 1, a photosensitive film 102 including a phosphor 101 and a protective film 103 deposited on upper and lower portions of the photosensitive film are illustrated.

The phosphor 101 includes (Gd, Y) 3 (Al, Ga) 5 O 12: Ce-based phosphors such as YAG: Ce, Y3Al5O12: Ce (YAG), and the like, and is not particularly limited to yellow, blue, and green. Or any phosphor material capable of being excited in the visible light wavelength band, such as red.

The photosensitive film 102 may be formed using any one material selected from polysiloxane, polyimide, polydimethylsiloxane, or acrylic resin.

The photosensitive film 102 including the phosphor 101 is cured into a polymer by chaining molecules of monomers in response to the UV band (360 nm to 405 nm), and may be maximized since light transmittance may be maximized. have.

In the present invention, the thickness of the photosensitive film 102 is preferably 10um to 100um.

The protective film 103 may be formed using any one of polyethylene terephthalate (PET), polybutylene terephthalate (PBT), or a polyester-based resin. Since these materials have characteristics of heat resistance, cold resistance, and chemical resistance, the photosensitive film 102 including the phosphor 101 may be protected from heat sources, pollutants, and the like to ensure high efficiency and high performance of semiconductor wafers including LED wafers. will be.

In the present invention, the thickness of the protective film 103 is preferably 100um to 500um.

Figure 2a is an example of the phosphor roll manufacturing apparatus according to an embodiment of the present invention.

In the present invention, the phosphor is pressed onto the semiconductor wafer using the phosphor roll 112 to facilitate the formation of the phosphor at the wafer level. Therefore, in order to perform the phosphor forming process, it can be said that manufacturing of the phosphor roll 112 is essential.

Referring to FIG. 2A, at least one transfer means for transferring the photosensitive film 110 including the phosphor and at least one protective film formed on or under the photosensitive film by passing the photosensitive film 110 including the phosphor therethrough. The phosphor roll manufacturing apparatus including the protective film roll 108 and the first roll 109 for producing the photosensitive film 111 having the protective film formed in the form of a roll is illustrated.

When the photosensitive film 110 including the phosphor is passed through the protective film roll 108 using a conveying means such as a conveyor belt, the protective film is formed on the upper and lower portions of the photosensitive film 110 including the phosphor. By the pressure of 108). At least one protective film roll 108 should be provided. In order to deposit the protective film on both the upper and lower surfaces of the photosensitive film, both the upper roll and the lower roll should be formed of a protective film roll.

In addition, according to the needs of the invention, a predetermined heat may be applied to the protective film roll 108 to further facilitate the deposition of the protective film.

The photosensitive film that has passed through the protective film roll 108 becomes a photosensitive film 111 having a protective film formed thereon, and is rolled using a first roll 109 to form a phosphor roll 112. The shape of the first roll 109 is sufficient as long as it can produce the photosensitive film 111, the protective film is formed in a roll form without particular limitation.

Therefore, the phosphor roll 112 is formed to include a protective film deposited on the upper and / or lower portion of the photosensitive film containing a phosphor therein.

2B to 2D are exemplary views illustrating a process of depositing a protective film on upper and lower portions of a photosensitive film including a phosphor according to an embodiment of the present invention.

Referring to FIG. 2B, the phosphor 101 is coated on the first photosensitive film 105, the second photosensitive film 106 is deposited on the phosphor 101, and the first photosensitive film 105 is then deposited. The cross-section of the phosphor roll formed by depositing the protective film 103 on the lower surface and the upper surface of the second photosensitive film 106 is shown step by step.

Of course, after depositing the second photosensitive film 106 on the phosphor 101, the protective film 103 will be formed through the protective film roll. In addition, the thickness of the first photosensitive film 105 and the second photosensitive film 106 is preferably 5um to 50um, respectively.

Referring to FIG. 2C, a form of the phosphor roll by the liquid phase mixing of the phosphor and the photosensitive resin is illustrated.

First, a phosphor and a thermosetting photosensitive resin are mixed and applied in a liquid phase on the protective film 103, and then precured using a predetermined heat. When the curing process is completed, the phosphor roll is formed by depositing the protective film 103 on the cured photosensitive film 107.

Different methods of curing phosphors and thermoset photosensitive resins include, but are not limited to, thermosetting, ultraviolet (UV) curing, infrared (IR) curing, air curing.

Of course, in the embodiment of Figure 2c is first applied to the protective film and the thermosetting photosensitive resin on the protective film, and then through the phosphor roll manufacturing apparatus is provided with a protective film roll on the top and a compression roll on the lower photosensitive film The protective film is to be deposited only on the upper surface of the.

Referring to FIG. 2D, a cross section of the phosphor roll formed using only the first photosensitive film without the second photosensitive film is shown.

That is, after the phosphor is coated on the first photosensitive film 105 and cured, the protective film 103 is formed on the upper and lower surfaces by passing the protective film roll.

3A is an exemplary view of a phosphor coating apparatus according to an embodiment of the present invention.

Referring to FIG. 3A, transfer means for transferring the plurality of semiconductor wafers 114 at regular intervals, and coating means for applying a phosphor to at least one surface of the semiconductor wafer; The phosphor coating device includes a phosphor roll 112 including a photosensitive film formed in a roll shape.

The transfer means is preferably a conveyor belt including a transfer conveyor 117, but is not necessarily limited thereto.

The coating means is a phosphor roll 112 which is located on the upper surface or the lower surface of the transfer means and the opposite side of the phosphor roll, the pressing roll 113 for applying pressure to deposit the photosensitive film containing the phosphor on the semiconductor wafer It is preferable to form, including).

As shown in FIG. 3A, a plurality of semiconductor wafers 114 are transferred at regular intervals by a conveyor belt or the like to pass through the phosphor roll 112 and the pressing roll 113, and the semiconductor wafer ( The photosensitive film and the protective film including the phosphor are deposited on at least one side of the 114).

Thus, since the wafer-level phosphor is formed only by passing the semiconductor wafer 114 between the phosphor roll 112 and the pressing roll 113, the manufacturing process is simple and mass production is advantageous.

3B is a plan view of a phosphor coating apparatus according to an embodiment of the present invention.

4A to 4C are exemplary views illustrating the formation of wire bonding pads on a semiconductor wafer according to an embodiment of the present invention.

FIG. 4A illustrates a photosensitive film 102 including a phosphor 101 and a protective film 103 formed on a semiconductor wafer 114 through the phosphor coating device. In order to form the wire bonding pad 118 here, the protective film 103 should be removed.

Referring to FIG. 4B, the protective film 103 is removed. The protective film 103 is a protective film 103 using any one drill selected from a laser drill, a CO2 drill, or a yag drill. Can be removed.

When the protective film 103 is removed as described above, the ultraviolet light (wavelength band is 360nm to 405nm) is irradiated, whereby the photosensitive film 102 including the phosphor is cured.

Referring to FIG. 4C, the predetermined region of the photosensitive film 102 including the phosphor is removed. The predetermined area should be removed in consideration of the formation of the wire bonding pad, and may be removed using any one drill selected from a laser drill, a CO 2 drill, or a yag drill.

5 is a flowchart illustrating a method of manufacturing a phosphor roll according to an embodiment of the present invention.

First, the phosphor is formed on or inside the photosensitive film. (S11)

The phosphor forming step is described in detail in the description of Figures 2b to 2d.

For example, the forming of the phosphor may include applying a phosphor on the first photosensitive film and depositing a second photosensitive film on the phosphor.

Here, it may be possible to deposit the protective film on the upper and lower sides after applying the phosphor on the first photosensitive film without depositing the second photosensitive film.

Thereafter, the photosensitive film including the phosphor is passed between the protective film rolls by a transfer means to form a protective film on the upper and lower portions of the photosensitive film.

The protective film roll may be appropriately heated to deposit the protective film, and according to the necessity of the invention, it may be possible to deposit the protective film only on one surface of the photosensitive film including the phosphor by having one protective film roll and a pressing roll. .

Thereafter, the protective film is formed by passing the photosensitive film formed on the first roll to form a phosphor roll. (S13) If the first roll can be formed by rolling a photosensitive film or the like in a roll without limiting its shape, Anything would be possible.

In the present invention, the forming of the phosphor (s11) and the forming of the protective film (s12) include the steps of applying a phosphor and a photosensitive resin on a protective film, curing the photosensitive resin containing the phosphor, and the photosensitive resin. It includes a method for producing a phosphor roll, characterized in that the pass through the protective film formed between the protective film roll to form a protective film on top of the photosensitive resin.

That is, as described above, after applying the photosensitive resin and the phosphor mixed in the liquid phase on the protective film, a method of forming a phosphor roll by passing between the protective film roll and the compression roll can also be employed.

6 is a flow chart of a phosphor coating method according to an embodiment of the present invention.

First, at least one semiconductor wafer is transferred through a phosphor roll and a compression roll to apply a photosensitive film and a protective film including the phosphor (s21).

When the semiconductor wafer passes through the phosphor roll and the compression roll, the photosensitive film and the protective film including the phosphor are deposited on one surface of the semiconductor wafer by a predetermined heat and pressure.

Thereafter, the protective film formed on the semiconductor wafer is removed.

The protective film serves to protect the phosphors from heat sources, pollutants, etc., thus removing them and proceeding to curing the photosensitive film containing the phosphors.

Thereafter, the step of irradiating the ultraviolet light on the semiconductor wafer (s23), the wavelength band of the ultraviolet ray is preferably 360nm to 405nm. When the ultraviolet light is irradiated, the photosensitive film including the phosphor is cured.

After the ultraviolet irradiation step (s23), the step of removing the predetermined region of the photosensitive film including the phosphor formed on the semiconductor wafer to form a wire bonding pad (s24).

In the wire bonding pad forming step, a wire bonding pad may be formed using any one drill selected from a laser drill, a CO 2 drill, or a yag drill. The wavelength range of the laser drill is 9,000nm to 10,000nm, the wavelength band of the CO2 drill is preferably about 360nm.

In this way, the phosphor coating method proposed in the present invention is completed when the wire bonding pad is passed through the step.

Although the present invention has been described in connection with the specific embodiments of the present invention, it is to be understood that the present invention is not limited thereto. Those skilled in the art can change or modify the described embodiments without departing from the scope of the present invention, and within the equivalent scope of the technical spirit of the present invention and the claims to be described below. Various modifications and variations are possible.

101: phosphor
102: photosensitive film
103: protective film
105: first photosensitive film
106: second photosensitive film
107: solution of phosphor and photosensitive resin
108: protective film roll
109: first roll
110: photosensitive film containing a phosphor
111: photosensitive film deposited with a protective film
112: phosphor roll
113: crimp roll
114: semiconductor wafer
115: transport belt
116: phosphor forming region in wafer units
117: conveying conveyor
118: wire bonding pad area

Claims (16)

delete delete delete delete delete delete delete delete delete delete delete delete Transferring at least one semiconductor wafer to pass through the phosphor roll and the compression roll to apply a photosensitive film and a protective film including the phosphor;
Removing the protective film formed on the semiconductor wafer; And
Forming a wire bonding pad by removing a predetermined region of the photosensitive film including the phosphor formed on the semiconductor wafer;
Phosphor coating method comprising a. The method of claim 13, after the protective film removing step,
And applying ultraviolet rays on the semiconductor wafer. 15. The method of claim 14, wherein the wavelength range of the ultraviolet ray is 360nm to 405nm. The method of claim 13, wherein the wire bonding pad forming step,
A method of applying a phosphor, characterized in that for forming a wire bonding pad using any one of the laser drill, CO2 drill or Yag drill.

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