WO2021010077A1 - Filament lamp for heating - Google Patents

Abstract

To provide a filament lamp for heating which allows the rising rate and falling rate of radiating energy to be increased, with a light-emitting section of the filament lamp being kept to a predetermined size, and is capable of rapidly increasing/decreasing the temperature of an object to be processed.　The filament lamp is characterized by having a filament having a double-coil structure in which a coil part formed by spirally winding parallelly arranged multiple strands about a first reference axis is spirally wound about a second reference axis different from the first reference axis.

Description

Filament lamp for heating

The present invention relates to a filament lamp for heating used as a heat source for heat treatment such as annealing treatment and drying treatment of an object to be treated (work).

Conventionally, in the heating process during semiconductor manufacturing, heat treatment using a plurality of filament lamps has been performed. Examples thereof include JP-A-2002-270533 (Patent Document 1) and JP-A-2015-050174 (Patent Document 2).
A heating device using such a filament lamp is required to heat-treat the surface of a work such as a semiconductor substrate uniformly for a short time, and RTP (Rapid Thermal) that raises and lowers the temperature of the object to be treated more rapidly. Processing) technology is required.
When the semiconductor wafer is heated at a predetermined temperature for a predetermined time, if the time required to raise the temperature to the predetermined temperature or the time required to lower the temperature from the predetermined temperature becomes long, the semiconductor wafer is heated even in the heating / lowering process, which is desired. This is because it becomes difficult to process with high accuracy in the heating process.

It is necessary to improve the lighting characteristics of the filament lamp, which is a heat source, in order to realize more rapid temperature rise and fall. For example, it is required to realize a more rapid ascending / descending temperature by shortening the rise time of radiant energy (light amount) or shortening the fall time of radiant energy (light amount).
On the other hand, in order to achieve effective heating, it is necessary to irradiate a predetermined range of light emitted from each light source of the filament lamp with a predetermined intensity. However, in order to realize such light distribution control, it is necessary to limit the light emitting portion of the filament lamp to a predetermined size (light emitting length in the longitudinal direction of the light emitting portion, width of the light emitting portion, etc.).

FIG. 7 shows a filament lamp used in such a heating device. For example, as shown in FIG. 7A, the light emitted from the light emitting portion (filament) 51 of the filament lamp 50 is a reflector 52. It is set to be reflected by and distributed in the desired irradiation range A1 indicated by the alternate long and short dash line in the figure.
At this time, even if another lamp having improved lighting characteristics is to be mounted on the heating device, the light emitting length M and the width (of the formed double coil) of the light emitting unit 51 shown in FIG. 7 (C) are used in the other lamp. If the outer diameter width) N changes, the irradiation range A2 changes as shown by the solid line in FIG. 7B, and there is a problem that it cannot be adopted.
Therefore, the size of the light emitting part (for example, the light emitting length and the light emitting width) of the filament lamp that can be mounted is restricted by the configuration of the heating device (for example, the shape of the reflector and the installation location of the light source), and even if the lamp with improved performance is used instead. , There is a problem that they must have the same irradiation area.

JP-A-2002-270533 Japanese Unexamined Patent Publication No. 2015-050174

The problem to be solved by the present invention is that in a filament lamp for heating, the rising speed and falling speed of radiant energy can be increased while maintaining the light emitting portion of the filament lamp at a predetermined size, and that of the object to be processed. It is an object of the present invention to provide a filament lamp for heating capable of realizing rapid ascending / descending temperature.

In order to solve the above problems, the heating filament lamp according to the present invention has a coil portion in which a plurality of strands arranged in parallel are spirally wound around the first reference axis. It is characterized by having a filament having a double coil structure formed by spirally winding around a second reference shaft different from the shaft.
Further, when the number of wires constituting the coil portion is n, the wire diameter is d, and the outer diameter of the coil portion is D, the filament has the following relational expression X = D / (n × d). It may be characterized by being in the range of.
(1) When n = 2, 2.7 ≤ X ≤ 4.3
(2) When n = 3, 2.5 ≤ X ≤ 4.0

Further, the ratio of the current value (I) flowing through the filament lamp to the wire weight (MG) per 200 mm of the wire constituting the filament may satisfy the following calculation formula.
I / MG ≧ 6.5
Further, the wire diameter (d) may be characterized in that it is formed in the range of 0.08 mm to 0.30 mm.
Further, the outer diameter (D) of the coil portion may be formed in the range of 0.8 mm to 2.0 mm.
Further, a first feeder line and a second feeder line are provided at the upper end portion and the lower end portion of the filament, respectively, and the strands constituting the coil portion are electrically connected to the feeder line. It may be characterized by being connected in parallel.

According to the heating filament lamp of the present invention, since the strands constituting the filament serving as the light emitting portion are composed of a plurality of thin strands, it is possible to realize rapid temperature rise and fall of the filament lamp.
Further, the filament constituting the light emitting portion has a double coil structure. That is, the coil portion in which a plurality of strands arranged in parallel are spirally wound around the first reference axis is spirally wound around the second reference axis different from the first reference axis. The filament has a double coil structure. As a result, even if the diameter or number of wires constituting the filament is changed, the light emitting length or width (outer diameter width) of the light emitting portion composed of the formed double coil can be adjusted to a desired size. This makes it possible to maintain the light irradiation range from the lamp within a desired range.

Sectional drawing of the filament lamp for heating of this invention. A first configuration example of the light emitting portion of the filament lamp of the present invention. A second configuration example of the light emitting portion of the filament lamp of the present invention. A table showing the I / MG ratio and the light intensity rise time with different numbers of strands. The graph which shows the relationship between the I / MG value of a filament and the light amount rise time. A graph showing the relationship between the number of strands and the rise time of the amount of light. Explanatory drawing of the conventional filament lamp for heating.

FIG. 1 is an overall cross-sectional view of the single-ended heating filament lamp 1 of the present invention, in which a filament 3 composed of a double coil (hereinafter referred to as a light emitting portion) is inside a sealed body 2 composed of a translucent member. The first feed line 4 and the second feed line 5 are provided at the upper end and the lower end of the double filament 3, and these feeder lines 4 and 5 are inside, respectively. It is wound around leads 6 and 7 and fixed.
These internal leads 6 and 7 are connected to the metal foils 10 and 11 embedded in the sealing portion 8, respectively, and are electrically connected to the external leads 12 and 13 via the metal foils 10 and 11, respectively. Has been done.

Details of an example of the double filament 3 are shown in FIG. 2, and in this example, as shown in FIG. 2 (B), the filament 3 constituting the light emitting portion is formed of two strands 3a and 3b. Each wire 3a and 3b is spirally wound to form a double coil structure.
More specifically, two strands 3a and 3b arranged in parallel are spirally wound around the first reference axis X to form a coil portion (primary coil portion) 3A, and further, FIG. As shown in A), the primary coil portion 3A is spirally wound around a second reference axis Y different from the first reference axis X to form a filament 3 having a double coil structure.
The strands 3a and 3b constituting these filaments 3 are electrically connected to the first feeder line 4 and the second feeder line 5 shown in FIG. 1 so as to be electrically parallel to each other.

The number of strands constituting the double filament 3 is not limited to the two shown in FIG. 2, and the number of strands can be further increased.
FIG. 3 shows a wire having three strands. As shown in FIG. 3B, three strands 3c, 3d, and 3e arranged in parallel are spirally wound around the first reference axis X to form a coil portion (primary coil portion) 3B. Is forming. At this time, the wire diameters d2 of the wires 3c, 3d, and 3e are smaller than the wire diameters d1 of the two wires 3a and 3b.
The outer diameter D2 of the primary coil portion 3B having a large number of wires (3 wires) and a thin wire diameter d2 has a small number of wires (2 wires) and is outside the thick primary coil portion 3A having a wire diameter d1. It is desirable that the diameter is smaller than D1, because the power densities of the primary coil portion 3B and the primary coil portion 3A per unit length of the filament 3 are controlled equally.

As shown in FIG. 3A, the coil portion (primary coil portion) 3B configured in this way is further spirally wound around a second reference axis Y different from the first reference axis X to be doubled. A filament 3 having a coil structure is formed.
At this time, both filaments (light emitting parts) 3 having different numbers of strands are aligned so that the light emitting length (filament length) L and the double coil (filament) outer diameter M are the same, respectively. The irradiation area from the light emitting unit 3 is the same.

The effects of the present invention will be described in detail below.
The inventors have conducted diligent studies, and in order to shorten (rapidly) the heating and lowering time of the filament in the filament lamp for heating, the heat capacity of the filament is reduced and the size of the light emitting portion is set to a desired size. I thought of an adjustable configuration. However, simply reducing the heat capacity of the filament may increase the amount of heat generated for the same amount of electric power and change the color temperature of the filament. If the color temperature changes, the amount of light absorbed by the object to be heated (workpiece such as a semiconductor wafer) changes, which makes the desired heat treatment more difficult.
Based on the above, it was decided to configure a plurality of strands constituting the filament.

By forming the filament with a plurality of strands, the one having a small diameter of each strand is selected when lighting with the same electric power. More specifically, a lamp having a small wire diameter is selected, and the power density per unit length of the entire filament is made equal to that of a conventional lamp having a filament composed of a single wire. At this time, since the surface area of the filament composed of a plurality of strands is larger than that of the filament composed of a single strand, the temperature tends to decrease, and the heat generation temperature of the filament decreases.
In consideration of this, by reducing the diameter of each wire of the filament (thinning the wire), it is possible to adjust the heat generation temperature to the same level as that of the filament of a single wire. On the other hand, when the cross-sectional area of the wire becomes smaller, the electric resistance of the wire increases and the electric power decreases. Therefore, it is necessary to shorten the length of the wire and adjust the resistance value.

As a result, when compared at the same power density and heat generation temperature, a filament composed of a plurality of strands can reduce the total amount of the entire filament with respect to a filament composed of a single strand, and the heat capacity can be reduced. I was able to reduce it. This makes it possible to realize a filament lamp in which the heating rate and the temperature decreasing rate of the filament are increased.

Further, by forming the filament in a double coil shape, it is possible to maintain a desired light emitting portion size without being affected by changes in the diameter and number of wires constituting the filament, so that the light irradiation region can be set. It is also possible to control to a desired range.
As described above, in the present invention, by arranging a plurality of strands constituting the filament in parallel with the filament having a double coil structure, the heat generation temperature is maintained at the same level as the conventional one, and as a result, It is possible to reduce the total amount (heat capacity) of the entire filament, and it is possible to maintain the same size of the light emitting portion while forming a plurality of strands, and to maintain a desired light irradiation region. There is an advantage. As the filament according to the present invention, for example, a filament having a light emitting length (L) of 20 mm to 40 mm and an outer diameter (M) of 4 mm to 10 mm can be used.

The biggest feature of the heating filament lamp according to the present invention is that rapid temperature rise and fall can be realized by forming the filament constituting the light emitting portion with a plurality of strands.
However, compared to the case where the filament is composed of a single wire, when the filament of the double coil is to be formed by a plurality of wires, the shape stability and workability of the double coil are large. It turned out to be different.

The wire diameter (d) of the strands that make up the filament, the outer diameter (D) of the coil part (primary coil) that is spirally wound around the first reference axis, and the number of strands that make up the filament. When the stability and workability of the shape of the double coil (secondary coil) were evaluated from the value of the index [D / (n × d)] determined by (n), the double coil with a single wire was used. It was found that the filament formed in the above had an index [D / (n × d)] value of 4.6 to 5.9.
If this index is less than 4.6, it becomes very difficult to process it into a coil shape, which tends to cause distortion or disconnection of the wire. On the other hand, if the index exceeds 5.9, the shape of the double coil structure becomes unstable, the filaments are displaced or bent, and there is a problem that the allowable range is deviated.

On the other hand, when the filament is formed into a double coil (secondary coil) by a plurality of strands as in the present invention, it is preferable that the outer diameter (D) of the coil portion (primary coil) is smaller. Become.
When the filament is used at the same predetermined power density and heat generation temperature as before, a thinner wire diameter (d) is selected as the number of wires (n) constituting the filament increases. It will be. Therefore, the index [D / (n × d)] of the filament composed of a plurality of filaments is good in different numerical ranges with respect to the filament of a single wire.

Based on the numerical value of the above index [D / (n × d)], the stability and workability of the coil shape when the filament is formed into a double coil structure with a plurality of strands (n = 2, 3). The evaluation was carried out. The evaluation results are shown in Tables 1 and 2.
Here, the shape stability of the double coil is a confirmation of the degree of maintenance of the shape of the coil, and the workability of the double coil is a confirmation of the processing limit when processing into a coil shape. Each was evaluated on a three-point scale according to the following procedure.

(Evaluation of coil shape stability)
◯: Those that can maintain their shape without deformation.
Δ: The shape is maintained within the permissible range.
X: The shape cannot be maintained within the permissible range.
(Evaluation of coil workability)
◯: Those that can be processed into a double coil shape.
Δ: Those that can be processed into a double coil shape depending on the processing conditions.
X: Those that break during processing.

First, as a double coil type filament to be evaluated, samples having an index [D / n × d] of 2.4 to 4.5 were prepared. Each sample has a filament emission length (L) of 30 mm and an outer diameter (M) of 7 mm, and the power density and heat generation temperature flowing through the filament are designed to be the same.
Next, in order to examine the shape stability of each filament, it was confirmed whether or not the shape was retained when each filament was erected vertically. Then, those in which the filament was held without displacement along the vertical direction were evaluated as ◯, and those in which the shape was maintained to the extent that the filament was slightly tilted with respect to the vertical direction but was within the allowable range were evaluated as Δ. More specifically, the case where the displacement amount of one end portion and the other end portion was within 2 mm when the filament was erected vertically was evaluated as Δ. Further, the case where the displacement amount in the vertical direction was larger than 2 mm and the shape retention was not recognized was evaluated as x, and each judgment was made.
Regarding workability, the one in which the wire breaks in the process of processing into a coil is evaluated as ×, and the wire is likely to break in the process of processing into a coil, but the processing conditions (coiling process, heat treatment conditions, etc.) ) Was evaluated, and those that could be processed into a coil shape were evaluated as Δ, and those that could be processed into a desired coil shape regardless of the processing conditions were evaluated as ◯. In addition, those that cannot be processed into a coil are marked with "-" because the shape stability cannot be evaluated.

From the results shown in Tables 1 and 2, the filament according to the present invention has a coil portion (primary coil) spirally wound around the outer diameter (d) of the strands constituting the filament and the first reference axis. The value of the index [D / (n × d)] determined by the outer diameter (D) of the above and the number of strands (n) constituting the filament must be within the following range according to the number of strands. It turns out that it is necessary.
(1) When n = 2, 2.7 ≤ X ≤ 4.3
(2) When n = 3, 2.5 ≤ X ≤ 4.0
It can also be seen that 2.7 ≤ X ≤ 4.0 indicates a common appropriate range even when the number of strands is different.

Further, in the filament lamp, the temperature rise of the filament differs depending on the relationship between the current value (I) flowing through the lamp and the wire weight (MG) constituting the filament, which affects the rise time of the amount of light generated from the filament. Here, when the wire weight constituting the filament is defined as the wire weight per 200 mm (MG), the current value (I) flowing through the filament lamp and the wire weight per 200 mm (MG) of the wire constituting the filament are used. ) And the ratio (I / MG) to the light intensity rise time of the filament.

More specifically, if a wire having a small wire weight (MG) per 200 mm can be used, the weight of the wire at the same resistance value is reduced, so that the heat capacity of the wire decreases and the filament temperature rises. This makes it easier to obtain the effect of increasing the rising speed of the amount of light. Similarly, as the heat capacity of the strands decreases, the temperature of the filament tends to decrease, and the effect of increasing the rising speed of the amount of light can be obtained.
In order to use a wire having a small wire weight (MG), the filament needs to be composed of a plurality of wires.

As described above, it can be understood that the ratio of the lamp current value to the wire weight (I / MG) shows a correlation with the rise time of the filament. Then, as the value of I / MG is increased, the temperature rising performance can be expected to improve.

FIG. 4 shows the I / MG ratios of the heating filament lamps shown in FIG. 1 when the number of strands is different for filaments designed with seven different specifications (power value, current value, color temperature). , Indicates the light intensity rise time.
Further, FIG. 5 shows the relationship between the ratio of the lamp current value and the weight of the filament wire (I / MG) and the light intensity rise time [ms] of the filament.
The rise time of the amount of light is the time from when the target filament lamp is continuously lit for 60 seconds and the amount of light after 60 seconds is set to 100% until the amount of light reaches 90%. , The amount of light was measured as the rise time.

As shown in FIG. 4, it can be seen that the I / MG value increases as the number of strands constituting the filament increases. This is because as the number of strands increases, the strands constituting the filament can be selected to have a lighter weight. Further, since the total weight of the filament also becomes lighter as the number of strands increases, improvement in the temperature rising performance can be expected.

Further, as shown in FIG. 5, when the ratio of the lamp current value to the weight of the filament wire (I / MG) and the change in the light intensity rise time [ms] of the filament are observed, the filament becomes larger as the I / MG value increases. It can be seen that the light intensity rise time becomes faster. It has also been shown that by adjusting the I / MG value to 6.5 or more, the light intensity rise time can be significantly shortened.
Therefore, the filament according to the present invention preferably has an I / MG value of 6.5 or more. As shown in FIG. 4, in order to control the I / MG value to 6.5 or more, it is necessary to set the number of strands constituting the filament to 2 or more.

Further, FIG. 6 shows the difference in the rising speed of the amount of light due to the change in the number of strands (n = 1 to 3) constituting the filament (light emitting portion) of the filament lamp. As shown in FIG. 6, as in the present invention, the filament composed of a plurality of strands has a faster light intensity rise speed than the filament composed of a single strand, and more specifically, the number of strands. It can be seen that the larger the number, the faster the light intensity rise speed.

By the way, the filament lamp applied to the present invention supplies at least 500 W or more of electric power, and more specifically, 500 to 2000 W of electric power.
From this point of view, the wire diameter (d) is preferably formed in the range of 0.08 mm to 0.30 mm.
If the wire diameter (d) is less than 0.08 mm, the current value flowing through the wires 3a to 3e becomes small and the heating efficiency drops, while if it exceeds 0.30 mm, the wire becomes too thick. This is because it becomes difficult to form a desired filament shape when processing into a double coil shape.

Further, the outer diameters (D) of the coil portions 3A and 3B are preferably formed in the range of 0.8 mm to 2.0 mm.
If the outer diameter (D) of the coil portion is less than 0.8 mm or more than 2.0 mm, it becomes very difficult to form a desired double coil shape.
The lamp of the present invention is intended to be compatible with conventional lamps, and in the filament lamp of the present invention, the double coil (filament) is matched to the emission size (filament) of the conventional lamp. is there.
However, if the outer diameter (D) of the primary coil (coil portion) is too small to be less than 0.8 mm, the length of the double coil (filament) becomes long, and if it becomes larger than 2.0 mm. , The length of the double coil (filament) becomes short. That is, if the outer diameter (D) of the coil portion is out of the range of 0.8 mm to 2.0 mm, it becomes impossible to create a double coil with a desired outer diameter and length. This is because compatibility with the lamp cannot be guaranteed.

As described above, according to the present invention, the coil portion obtained by spirally winding a plurality of strands of filaments in a heating filament lamp arranged in parallel around the first reference axis is the first. By adopting a double coil structure in which the filament lamp is spirally wound around a second reference shaft, which is different from the first reference shaft, it is possible to realize a rapid ascending / descending temperature of the filament lamp.
Further, even if the diameter or number of the wires constituting the filament is changed, the light emitting length and width (outer diameter of the formed double coil) of the light emitting portion (filament) can be adjusted to a desired size. This also has the effect of maintaining the light irradiation range from the lamp within a desired range.

1: Filament lamp for heating 2: Sealed body 3: Filament 3a to 3e: Wire d: Wire diameter 3A, 3B: Coil part (primary coil)
D: Outer diameter of coil part L: Emission length (filament length)
M: Filament (double coil) outer diameter 4: First feed line 5: Second feed line 6, 7: Internal lead 8: Sealing part 10, 11: Metal leaf 12, 13: External lead X: First reference Axis Y: Second reference axis

Claims (6)

1. A coil part in which a plurality of strands arranged in parallel are spirally wound around the first reference axis.
   A filament lamp for heating, which has a filament having a double coil structure formed by spirally winding around a second reference shaft different from the first reference shaft.
2. When the number of wires constituting the coil portion is n, the wire diameter is d, and the outer diameter of the coil portion is D, the filament has the following range of relational expression X = D / (n × d). The heating filament lamp according to claim 1.
   (1) When n = 2, 2.7 ≤ X ≤ 4.3
   (2) When n = 3, 2.5 ≤ X ≤ 4.0
3. The first aspect of the present invention, wherein the ratio of the current value (I) flowing through the filament lamp and the wire weight (MG) per 200 mm of the wire constituting the filament satisfies the following calculation formula. Filament lamp for heating.
   I / MG ≧ 6.5
4. The heating filament lamp according to claim 2, wherein the wire diameter (d) is formed in the range of 0.08 mm to 0.30 mm.
5. The heating filament lamp according to claim 2, wherein the outer diameter (D) of the coil portion is formed in the range of 0.8 mm to 2.0 mm.
6. A first feed line and a second feeder are provided at the upper end and the lower end of the filament, respectively, and the strands constituting the coil portion are electrically parallel to the feeder. The heating filament lamp according to claim 1, wherein the filament lamp is connected.

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