JP2023075388A - Led lamp for heating and heating device having the same - Google Patents

Abstract

To provide an LED lamp for heating capable of reducing damage caused by radiant energy from a material to be heated.SOLUTION: An LED lamp 100 is configured by an LED module 102 having a substrate 110 and a plurality of LEDs 120 arranged on a surface of the substrate 110, and a first filter 104 and a second filter 106 arranged between the LED module 120 and a material W to be heated. The first filter 104 has cutoff characteristics at a wavelength longer than that of light emitted from the LED 120. The second filter 106 has cutoff characteristics at a wavelength longer than a wavelength of light and at a wavelength shorter than that of the first filter 104.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to an LED lamp for heating a material to be heated, such as a wafer, and a heating device including the same.

2. Description of the Related Art Conventionally, an apparatus for heating a wafer for semiconductor manufacturing with an LED lamp has been proposed (for example, Patent Document 1 and Patent Document 2).

In addition, in the semiconductor manufacturing process, for the purpose of screening for initial defective products, "burn-in" may be performed in which the completed semiconductor is subjected to a load with a voltage and operating frequency higher than the maximum rating and then further heated. It has also been proposed to use an LED lamp for heating during this burn-in (for example, Patent Document 3).

In addition, since LED lamps have advantages such as fast response speed and excellent dimming controllability, the use of LED lamps in other heating processes where conventional halogen lamps have been used has been studied. ing. This "other heating process" includes, for example, resist cure, oxidation treatment, annealing treatment under vacuum or pressure, and the like.

JP 2012-178576 A (dome type) Japanese Patent Publication No. 2005-536045 (cannonball type) Japanese Patent Application Laid-Open No. 2002-208620

However, when an LED lamp is used as a heat source, the light from the LED lamp generally spreads (has a wider beam angle) than other heat sources. In order to do so, it is necessary to bring the LED lamp and the material to be heated as close as possible to reduce irradiation loss to the material to be heated.

Then, as the distance between the LED lamp and the material to be heated becomes closer, the amount of radiant energy that the LED lamp receives from the heated material to be heated increases, and the surface of the LED lamp is greatly damaged. There was a problem of what was going on.

The present invention has been made in view of the above problems, and its object is to provide a heating LED lamp that can reduce damage due to radiant energy from a material to be heated, and a heating device equipped with the same. That's what it is.

According to one aspect of the invention,
an LED module comprising a substrate and a plurality of LEDs disposed on a surface of the substrate;
An LED lamp comprising a first filter and a second filter positioned between the LED module and a material to be heated,
The first filter has a cutoff characteristic at a wavelength longer than the wavelength of light emitted from the LED,
The LED lamp is provided, wherein the second filter has cutoff characteristics at wavelengths longer than the wavelength of the light and shorter than the wavelength of the first filter. .

Preferably,
The wavelength of the light emitted from the LED is a near-infrared light wavelength close to visible light.

Preferably,
The first filter is either one of glass and an optical filter,
The second filter is either one of glass and an optical filter.

Preferably,
The first filter and the second filter are configured such that their surfaces are in contact with each other.

Preferably,
A third filter having a cutoff characteristic at a wavelength different from that of the first filter and the second filter is provided.

Preferably,
At least one of the first filter and the second filter is a lens that refracts the light emitted from the LED toward the heated material.

According to another aspect of the invention,
A heating device is provided comprising an LED lamp as described above.

According to the heating LED lamp according to the present invention, the light emitted from the LED passes through the first filter and the second filter arranged between the LED module and the material to be heated, and passes through the material to be heated. to heat the material to be heated.

Radiant light is radiated from the material to be heated by being heated by the light emitted from the LED. However, since the radiant light has a longer wavelength than the light from the LED, it is cut by the first filter and the second filter, so that the radiant light reaching the LED can be reduced.

It is a figure which shows the LED lamp 100 based on embodiment to which this invention was applied. It is a figure which shows the relationship between the wavelength of light, and each infrared-light area|region. FIG. 10 is a diagram showing an LED lamp 100 according to another embodiment; FIG. 10 is a diagram showing an LED lamp 100 according to another embodiment; FIG. 10 is a diagram showing an LED lamp 100 according to another embodiment; FIG. 10 is a diagram showing an LED lamp 100 according to another embodiment; It is a figure which shows the heating apparatus which concerns on embodiment to which this invention was applied. It is a figure which shows the heating apparatus which concerns on another form. It is a figure which shows the heating apparatus which concerns on another form.

(Structure of LED lamp 100 for heating)
A heating LED lamp 100 to which the present invention is applied will be described with reference to the drawings. FIG. 1 is a diagram showing an LED lamp 100 according to this embodiment.

The LED lamp 100 according to this embodiment is generally composed of an LED module 102, a first filter 104, and a second filter 106. As shown in FIG.

The LED module 102 is composed of a substrate 110 , a plurality of LEDs 120 arranged on the surface of this substrate 110 and a heat sink 122 . It should be noted that "arranged" here means that each LED 120 is mounted on the surface of the substrate 110 if, for example, each LED 120 is of a Chip On Board (COB) type. Of course, the LED module 102 is not limited to the COB type, and may be of other types.

Further, each LED 120 may emit light of a single wavelength from a die, or may emit light of a wider wavelength (broad wavelength) via a phosphor or the like.

Furthermore, if the temperature of the LED 120 itself rises too much, problems may occur with the LED module 102, such as a change in the wavelength of emitted light or a decrease in the amount of light emitted. Therefore, as in the present embodiment, a sheet material or the like (not shown) with high heat dissipation is provided on the back surface of the substrate 110 (the surface opposite to the surface on which the LEDs 120 are arranged (mounted)). Preferably, the LED 120 is cooled by a heat sink 122 against a material or the like. The heat sink 122 may be water-cooled, or may be air-cooled if the LEDs 120 do not exhibit a temperature rise sufficient to be water-cooled.

Also, it is preferable to use a combination of a plurality of LED lamps 100 (or LED modules 102; the same shall apply hereinafter) according to the size of the wafer (material to be heated) W to be heat-treated. By using a plurality of LED lamps 100 that are small to some extent (a small number of LEDs 120 are mounted) instead of one large LED lamp 100 (a large number of LEDs 120 are mounted), the wafer (material to be heated) This is because the amount of heat to be applied to W can be easily adjusted, and a region in which a large amount of heat is applied and a region in which a small amount of heat is applied can be intentionally divided according to need.

As for the material of the substrate 110, as described above, in order to prevent the temperature of the LED 120 itself from rising too much, the substrate 110 may be an aluminum-based substrate or a copper-based substrate with low thermal resistance. Alternatively, it is desirable to use an alumina substrate or an aluminum nitride substrate. In addition, as the size of the substrate 110 increases, the coefficient of thermal expansion of metals such as aluminum and copper and the coefficient of thermal expansion of the resin resist that fixes the LED 120 to the substrate will increase in the case of a metal substrate based on aluminum or copper. There is a problem that the substrate 110 is warped due to the difference in the thickness. Therefore, when the size of the substrate 110 is large, it is preferable to use a ceramic substrate such as an alumina substrate or an aluminum nitride substrate which does not cause such problems.

Also, it is preferable to use a double-junction chip having two light-emitting layers for the LED 120 . As a result, the light emission amount (heating amount) per unit area of the LED module 102 can be increased.

Moreover, it is conceivable that the mounting arrangement shape of the LEDs 120 on the substrate 110 is a grid pattern or a houndstooth pattern so that the intervals between the LEDs 120 are constant.

By the way, the wavelength of the light emitted from the LED 120 in the LED module 102 is preferably 700 nm or more and 1000 nm or less, which is a near-infrared light wavelength close to visible light (see FIG. 2).

The reason for this is as follows. First, light with a short wavelength of 400 nm or less is largely absorbed by the sealing silicone resin used when placing and mounting the LED 120 on the substrate 110. This is not desirable because the silicone resin for the wafer W deteriorates severely, and the absorption rate of the wafer W is relatively low and the temperature rising effect is low. Conversely, long-wavelength light of 1000 nm or longer significantly reduces the absorptance of the wafer W (transmits through the wafer W), so the effect of raising the temperature of the wafer W cannot be expected, which is undesirable.

From the above, it is possible to use the wavelength of the light emitted from the LED 120 in the range of 400 nm to 1000 nm.

Returning to FIG. 1, the first filter 104 and the second filter 106 will now be described. In this embodiment, a quartz glass (glass) plate material is used as the first filter 104, and an optical filter in which the surface of the first filter 104 is coated is used as the second filter 106.

The first filter 104 is a member having a characteristic (cutoff characteristic) of absorbing or reflecting wavelengths on the longer wavelength side than the wavelength of light emitted from each LED 120 . For example, in the present embodiment, as described above, the wavelength of the light from the LED 120 is 700 nm or more and 1000 nm or less, whereas the first filter 104 using quartz glass has a wavelength of 2600 nm or more (far infrared light: 2) is absorbed or reflected (cutoff characteristics).

The second filter 106 has a characteristic (cut) that absorbs or reflects wavelengths on the longer wavelength side than the wavelength of light emitted from each LED 120 and on the lower wavelength side than the first filter 104 described above. off characteristics). For example, in this embodiment, it has a characteristic (cutoff characteristic) of absorbing or reflecting light of wavelengths from 1000 nm to 2000 nm or longer (from near-infrared light to mid-infrared light: see FIG. 2).

Of course, another optical filter may be used as the first filter 104 and glass as the second filter 106 . Also, both the first filter 104 and the second filter 106 may be optical filters. The optical filter may be one coated on the surface of quartz glass as described above, one coated on the surface of soda glass, or made of resin.

In this embodiment, the second filter 106 is arranged (coated) on the surface of the plate-shaped first filter 104 facing the LED 120 . More specifically, the first filter 104 and the second filter 106 are configured such that their surfaces are in contact with each other.

Alternatively, the second filter 106 may be arranged (coated) on the surface of the plate-like first filter 104 facing the wafer (material to be heated) W. FIG.

Further, as shown in FIG. 3, the first filter 104 and the second filter 106 (for example, plate-shaped quartz glass + coating) may be configured as separate members. At this time, the second filter 106 may be positioned closer to the LED 120 than the first filter 104 as shown, or conversely, the first filter 104 may be positioned closer to the LED 120 than the second filter 106. It can be placed in close proximity.

Furthermore, a third filter 108 having characteristics (cutoff characteristics) of absorbing or reflecting wavelengths different from those of the first filter 104 and the second filter 106 may be further provided. For example, as shown in FIG. 4, the second filter 106 (cutoff wavelength is 1000 nm) is placed (coated) on the upper surface of the glass plate that is the first filter 104 (the surface facing the LED 120), and the first filter It is conceivable to dispose (coate) a third filter 108 (with a cutoff wavelength of 1200 nm) on the lower surface of 104 (the surface facing the material W to be heated). Also, the first filter 104, the second filter 106, and the third filter 108 may be configured separately.

Alternatively, for example, as shown in FIG. 5, two glass plates that are the first filter 104 are prepared, and the second filter 106 is placed (coated) on the upper surface (or the lower surface) of one of the glass plates, and the other is coated. A third filter 108 may be placed (coated) on the upper surface (or the lower surface) of the glass plate of the , and disposed between the LED module 102 and the material W to be heated. In this case, either the second filter 106 or the third filter 108 can be placed near the LED module 102 .

The characteristic (cutoff characteristic) of absorbing or reflecting light of the third filter 108 is on the longer wavelength side than the wavelength of the light from the LED 120, on the lower wavelength side than the first filter 104, and , is preferably at a different wavelength than the second filter 106 .

More specifically, as shown in FIG. 6, a plurality of quartz glass materials that are bent to form convex lenses are provided with second filters 106 on their respective surfaces, and these second filters 106 are arranged in the vicinity of each LED 120 . A quartz glass plate as the first filter 104 may be arranged between 106 and the material W to be heated. At this time, each second filter 106 may correspond to one LED 120 , or one second filter 106 may correspond to a plurality of LEDs 120 .

Next, an example of a heating device 200 for burning-in a wafer (material to be heated) W using the plurality of heating LED lamps 100 described above will be described. As shown in FIG. 7, the heating device 200 generally includes the plurality of LED lamps 100 described above, the heating furnace body 210, the wafer table 220, the LED lamp controller 230, the vacuum pressurization controller 240, and the wafer. A tester 250 is provided.

The heating furnace body 210 is a box-shaped body having an opening 212 at its lower end in the drawing, and a plurality of LED lamps 100 are arranged above its internal space 214 . In addition, at the lower end of the heating furnace body 210, a wafer holder 216 holds a wafer (member to be heated) W to be burned-in and hermetically seals the inner space 214 while holding the wafer (member to be heated) W. is formed. Furthermore, a pressure adjustment hole 218 for adjusting the pressure in the airtight internal space 214 is formed in the heating furnace body 210, and the pressure adjustment hole 218 is connected to a vacuum pressurization control device 240. there is A combination of the heating furnace body 210 and the LED lamp 100 is called a "heating device".

The wafer table 220, on which a wafer (member to be heated) W to be burn-in is placed, supplies a predetermined voltage and current to the circuit formed on the placed wafer (member to be heated) W. It is an apparatus for testing a wafer (member to be heated) W by means of The wafer table 220 is electrically connected to a wafer tester 250 , and the wafer (member to be heated) W is tested and controlled by this wafer tester 250 .

The LED lamp control device 230 supplies power to each of the plurality of LED lamps 100 arranged in the heating furnace body 210, adjusts and controls the current value and the like for each LED lamp 100, and controls the wafer (member to be heated). This is a device that supplies a uniform and optimal amount of heat to W.

The vacuum pressurization control device 240 is a device for controlling the pressure in the internal space 214 of the heating furnace body 210, and when the wafer (member to be heated) W is burned-in, the pressure in the internal space 214 becomes higher than the atmospheric pressure. is controlled as Of course, the internal space 214 may be controlled to be vacuum.

(Distance between LED lamp 100 for heating and wafer (material to be heated) W)
The distance between the heating LED lamp 100 and the wafer (material to be heated) W should be 1 mm or more, but if it is too short, the uniformity of heating of the wafer (material to be heated) W becomes disadvantageous. Therefore, it should be at least 3 mm or more, preferably 5 mm or more, more preferably 10 mm or more.

(Regarding Gas Filled in Internal Space 214 of Heating Furnace Body 210)
The gas that fills the internal space 214 of the heating furnace body 210 is preferably air, nitrogen, or an inert gas.

(Heating capacity of heating device 200)
As for the heating capacity of the heating device 200, the wafer (material to be heated) W can be heated to 200° C. or higher and 500° C. or lower. It is preferable that the temperature of the wafer (material to be heated) W itself can be heated to the above temperature in a time of 2 seconds or more and 5 seconds or less.

The heating furnace body 210 is not limited to the one described above. For example, as shown in FIG. . In the illustrated example, the internal space 214 and the light source space 219 are airtightly separated by the first filter 104 .

By airtightly separating the internal space 214 controlled by vacuum or pressurization and having a high temperature and the light source space 219 in which the LED module 102 is arranged, a cooling gas inlet 222 is provided in the light source space 219. The LED module 102 can be cooled to an appropriate temperature by, for example, injecting an appropriate cooling gas through the cooling device.

Further, when using the LED lamp 100 in which the first filter 104 and the second filter 106 are separately configured as shown in FIG. configuration.

(Features of LED lamp 100 for heating)
According to the LED lamp 100 according to this embodiment, the light emitted from the LED 120 passes through the first filter 104 and the second filter 106 arranged between the LED module 102 and the material to be heated. It reaches the heating material and heats the material to be heated.

Radiant light is emitted from the material to be heated by being heated by the light emitted from the LED 120 . However, since the radiant light has a longer wavelength than the light from the LED 120, it is cut by the first filter 104 and the second filter 106, so that the radiant light reaching the LED 120 can be reduced.

It should be considered that the embodiments disclosed this time are illustrative in all respects and not restrictive. The scope of the present invention is indicated by the scope of the claims rather than the above description, and is intended to include all modifications within the scope and meaning equivalent to the scope of the claims.

DESCRIPTION OF SYMBOLS 100... LED lamp for heating, 102... LED module, 104... 1st filter, 106... 2nd filter, 108... 3rd filter, 110... Substrate, 120... LED, 122... Heat sink 200... Heating device 210 Heating furnace body 212 Opening 214 Interior space 216 Wafer holder 218 Pressure adjustment hole 219 Light source space 220 Wafer table 222 Cooling gas inlet 230 LED lamp controller 240 Vacuum Pressurization control device 250... Wafer tester W... Material to be heated (wafer)

Claims (7)

an LED module comprising a substrate and a plurality of LEDs disposed on a surface of the substrate;
An LED lamp comprising a first filter and a second filter positioned between the LED module and a material to be heated,
The first filter has a cutoff characteristic at a wavelength longer than the wavelength of light emitted from the LED,
The LED lamp, wherein the second filter has cutoff characteristics at wavelengths longer than the wavelength of the light and shorter than the wavelength of the first filter. The LED lamp according to claim 1, wherein the wavelength of the light emitted from the LED is a near-infrared light wavelength close to visible light. The first filter is either one of glass and an optical filter,
3. The LED lamp according to claim 1, wherein said second filter is the other of glass and an optical filter. The LED lamp according to any one of claims 1 to 3, wherein the first filter and the second filter are configured such that their surfaces are in contact with each other. 5. The LED lamp according to any one of claims 1 to 4, further comprising a third filter having cutoff characteristics at wavelengths different from those of said first filter and said second filter. At least one of the first filter and the second filter is a lens that refracts the light emitted from the LED toward the material to be heated. LED lamp. A heating device comprising the LED lamp according to any one of claims 1 to 6.

Images