JP4981477B2 - Vacuum processing apparatus and substrate heating method - Google Patents

Description

  The present invention relates to a vacuum processing apparatus.

Solar cells that generate electricity in response to light are known. As one of them, a thin-film silicon solar cell in which a power generation layer of amorphous silicon or microcrystalline silicon is formed on a large substrate is known. When manufacturing such a solar cell, it is important to form a uniform thin film silicon over the entire surface of a large substrate (example: 1 m × 1 m or more). In that case, it is necessary to uniformly raise the substrate temperature over the entire surface of the substrate in order to preheat the substrate to be brought into the thin film silicon deposition apparatus to near the deposition temperature. Moreover, it is necessary to rapidly raise the temperature in a short time so that the tact time required for the treatment is not extended. Therefore, the substrate is heated in the load chamber adjacent to the film forming chamber using an infrared lamp type heater (hereinafter referred to as IR heater) having a large heat generation density.
JP-A-6-260422 JP-A-2005-231910 JP-A-3-274275

However, a transparent conductive film (TCO film) is formed on a substrate for a thin film silicon-based solar cell, and when a glass substrate with a transparent conductive film (TCO film) is heated by a conventional IR heater, the temperature of the substrate is increased within a predetermined time. There were limits to improvements in speed and heating temperature. For this reason, when a temperature measurement test and thermal analysis were performed, it was found that only about 20% of the input power mainly composed of radiant heating by a halogen light source contributes to substrate heating. This is done by installing a light source on the transparent conductive film (TCO film) side in order to heat the glass substrate with the transparent conductive film (TCO film) uniformly without being affected by the substrate support member. This is because the emission wavelength range from the IR heater does not match the reflection of the transparent conductive film (TCO film) and the light absorption wavelength characteristic of the glass. In this situation, in order to further improve the heating temperature rise characteristic of the substrate, it is necessary to use a large-capacity IR heater, and there are problems in increasing the size and cost of the apparatus.
On the other hand, the long-wavelength heater in Patent Document 1 has improved heat absorption characteristics to the glass plate, but the heat generation density for rapid heating is insufficient and expensive, and the far-infrared radiator of Patent Document 2 has a structure. However, the heater disclosed in Patent Document 3 is complicated and expensive due to the configuration in which pulse light is used to suppress an increase in ambient temperature. Furthermore, none of the heaters of the patent documents has a structure that takes into consideration the heat absorption / reflection characteristics of the transparent conductive film (TCO film).

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a vacuum processing apparatus capable of heating a substrate rapidly and uniformly by using input power efficiently even for a large substrate.

The vacuum processing apparatus according to claim 1 includes a chamber for processing a glass substrate in a state where the pressure is reduced from atmospheric pressure, and a heater for heating the glass substrate in the chamber, and the heater for the glass substrate; Comprises a black radiating plate provided on the opposite side, the black radiating plate being a foil plate provided apart from the wall surface of the chamber, and mainly the glass substrate among the radiant rays emitted from the heater. permeated by Ri is heated pressurized to light, characterized in that it emits radiation of far infrared rays and a main heating the glass substrate from the side opposite to the heater.

Radiation rays emitted from the heater directly heat the glass substrate with wavelengths in the infrared region, but most of light with a wavelength of 1.5 μm or less passes through the glass substrate, and some wavelengths are longer than this. Penetrates the glass substrate. In the present invention, the black radiation plate is heated mainly using radiation rays that have passed through the glass substrate. That is, in the present invention, the black radiating plate does not simply convert the infrared rays emitted from the heater into a long wavelength, but converts the light on the short wavelength side transmitted through the glass substrate into a wavelength that can be absorbed by the glass substrate. Is. Although there is radiation light that does not pass through the glass substrate and is reflected by the internal structure of the vacuum processing chamber to heat the black radiation plate, from the positional relationship between the glass substrate, the heater, and the black radiation plate, the glass substrate The transmitted radiation beam contributes most of the heating of the black radiation plate.
Thus, the glass substrate is heated by the radiant heat from the black radiation plate. The black radiation plate is preferably heated by a heater, for example, an IR heater, so that infrared rays having a wavelength that is easily absorbed by the glass substrate are emitted. More specifically, it is desirable that infrared rays having a wavelength of 2.8 μm or more, more preferably 3.0 μm or more, and a short wavelength side with high energy are emitted. Further, it is desirable to heat the black radiation plate to about 400 ° C. so that about 4 μm of infrared rays is emitted. With this configuration, the glass substrate is heated from the back side (the surface opposite to the heater) by radiation from the black radiation plate.
Here, the infrared rays include near infrared rays, middle infrared rays, and far infrared rays, and electromagnetic waves having a wavelength of about 0.8 μm to about 100 μm are targeted.

  According to a second aspect of the present invention, in the vacuum processing apparatus according to the first aspect, a transparent conductive film (TCO film) is formed on at least a part of the surface of the glass substrate, and the radiation light emitted from the heater is emitted. Among them, the peak wavelength having the highest radiation intensity in the infrared region is a wavelength that is not reflected by 80% or more by the transparent conductive film (TCO film).

More specifically, the wavelength that is not reflected by the transparent conductive film (TCO film) is preferably a wavelength of 3.0 μm or less, and more preferably a wavelength of 2.8 μm or less. The wavelength that can be absorbed by the glass substrate on which the transparent conductive film (TCO film) is formed is preferably 1.5 μm or more. The peak with the highest radiation intensity among the irradiation wavelengths of the IR heater can be controlled by changing the heating wire diameter and length. According to the present invention, the proportion reflected by the transparent conductive film (TCO film) is reduced, and the contribution ratio of the input power to the glass substrate heating is improved.
In addition, light having a wavelength reflected by the transparent conductive film (TCO film) mainly reflects from the surface on the incident light side of the transparent conductive film (TCO film), but a part of the light is reflected by the transparent conductive film (TCO film). There is also reflection from the interface between the film) and the glass substrate, and both of them are included.

  According to a fourth aspect of the present invention, in the vacuum processing apparatus according to any one of the first to third aspects, a reflective plate is provided at a position opposite to the glass substrate with respect to the black radiation plate. Features.

According to the present invention, the amount of heat escaping to the chamber wall surface can be reduced, and the temperature of the black radiation plate can be increased. This increases the heat transfer to the glass substrate. As the temperature of the black radiation plate rises, the shorter wavelength side can be emitted, and the heating contribution rate to the glass substrate is improved.
It should be noted that the emissivity is preferably 0.2 or less so that the emissivity of the reflector is lower than the emissivity of the surrounding structure. Further, in order to reduce the amount of heat that escapes to the chamber wall surface while keeping the reflector surface temperature high. You may provide more than one.

  The invention according to claim 5 is the vacuum processing apparatus according to claim 4, wherein the side facing the glass substrate is the black radiation plate, and the back side of the black radiation plate is the reflector. It has the board | plate material which hold | maintained.

  For example, one side of a single metal plate (SUS material or the like) on the glass substrate side is made a black radiation surface by anodizing or the like, and the back side is polished to make a reflection surface. As a result, the number of parts is reduced, and in addition to the cost reduction of the part main body, the surface area of the additional parts is reduced. Therefore, the amount of degassing from the surface of the internal structure of the chamber is suppressed, and the reduction of the vacuum exhaust speed can be suppressed.

  According to a sixth aspect of the present invention, in the vacuum processing apparatus according to any one of the first to fifth aspects, at least within a range surrounding the heater, the glass substrate, and the black radiation plate on the inner wall surface of the chamber. A reflection plate is provided in part.

Thereby, the amount of heat escaping to the chamber wall surface is reduced, and the temperature of the black radiation plate can be further increased. This increases the amount of heat transfer to the glass substrate. When the temperature of the black radiation plate rises, it becomes possible to emit infrared rays having shorter wavelengths, and the heating contribution ratio to the glass substrate is improved.
In addition, it is effective in heating the glass substrate to a uniform temperature distribution by the reflected light from the periphery of the inner wall of the chamber. In particular, the wavelength (approximately 3.0 μm or more) reflected from the transparent conductive film (TCO film) is reflected from the periphery of the inner wall of the chamber to be incident on the black radiation plate. Thereby, the glass substrate heating efficiency can be increased.

  The invention according to claim 7 is the vacuum processing apparatus according to any one of claims 1 to 6, wherein a second black radiation plate is provided at a position opposite to the glass substrate with respect to the heater. It is characterized by that.

  In particular, the second black radiation plate has a wavelength that passes through the transparent conductive film (TCO film) without being absorbed and can be partially absorbed by the glass substrate, and has a low reflection at the transparent conductive film (TCO film). It is preferable to radiate at (2.5 μm to 3.0 μm). According to the present invention, the glass substrate can be heated from the whole of the front surface side and the back surface side, and the amount of infrared rays input to the glass substrate is made more uniform, the glass substrate becomes more uniform temperature distribution, and the glass substrate heating efficiency is improved. In addition to this, it may also be installed on a surface (lateral side) extending in a direction intersecting the glass substrate surface.

  According to the vacuum processing apparatus according to the present invention, by heating the glass substrate from the back surface with the black radiation plate, the glass substrate can be heated more uniformly in a short time using the input power efficiently.

[First Embodiment]
FIG. 1 shows a thin film manufacturing apparatus (vacuum processing apparatus) 1 that forms a silicon film on a substrate (glass substrate) 8 when a semiconductor such as a silicon solar cell is manufactured. In addition, the board | substrate 8 shows the glass substrate in which the transparent conductive film (TCO film | membrane) was formed in the single side | surface of a glass plate. Reference numeral 6 denotes a film forming chamber, which can maintain a state where the pressure is reduced from the atmospheric pressure with almost no air mixed therein, and high-quality film forming processing is possible. Reference numeral 21 denotes a substrate transfer device ( When loading into the film forming chamber 6 using a not-shown), a load chamber 22 between the film forming chamber 6 and the unload chamber 22 for unloading the substrate 8 from the film forming chamber 6 is used. The substrate 8 has a transparent conductive film (TCO film) 8a formed on one side of a glass plate 8b. In some cases, a photoelectric conversion layer (with a p-layer, i-layer, and n-layer laminated) formed of a silicon-based thin film may be formed on the transparent conductive film (TCO film) 8a. Since the photoelectric conversion layer is hardly absorbed by the silicon thin film with respect to radiated light of .5 μm or more, light absorption / reflection characteristics similar to those of the substrate 8 having the transparent conductive film (TCO film) 8a formed on one side surface are exhibited. . The film forming chamber 6, the load chamber 21 and the unload chamber 22 are provided with chambers 6a, 21a and 22a, respectively. These chambers 6a, 21a and 22a are respectively roughing pumps 23a, 23b and 23c and turbo molecular pumps 24a and 24b. , 24c, a high vacuum state is obtained. Each chamber is partitioned by a gate valve 25, and the pressure in each chamber can be set. The entire apparatus is controlled by the control apparatus 100.

  FIG. 2 shows the structure of the film forming chamber 6. In the film forming chamber 6, the counter electrode 2, the soaking plate 5, the soaking plate holding mechanism 11, the discharge electrode 3, the deposition preventing plate 4, the support portion 7, the high-frequency power transmission path 12, the matching unit 13, and high vacuum exhaust Part 31, a low vacuum exhaust part 35, and a base 37. In addition, in this figure, the structure regarding gas supply is abbreviate | omitted.

  The film forming chamber 6 is a vacuum container, and forms a microcrystalline silicon i layer or the like on the substrate 8 inside. The film forming chamber 6 is held on the table 37 while being inclined by θ = 7 ° to 12 ° with respect to the z direction (vertical direction). For this reason, the film-forming surface of the substrate 8 of the counter electrode 2 faces 7 ° to 12 ° above the z direction. By slightly tilting the substrate 8 from the vertical, the substrate 8 can be held with less effort using the weight of the substrate 8 while suppressing an increase in the installation space of the apparatus, and the adhesion between the substrate 8 and the counter electrode 2 is improved. This is preferable because the temperature distribution and potential distribution of the substrate 8 can be made uniform.

  The counter electrode 2 is an electrode (example: ground side) facing the discharge electrode 3. The counter electrode 2 has one surface in close contact with the surface of the soaking plate 5 and the other surface in close contact with the surface of the substrate 8 during film formation. The soaking plate (means for controlling the temperature of the counter electrode) 5 circulates a temperature-controlled heat medium inside or incorporates a temperature-controlled heater to control its own temperature, and the whole It has a uniform temperature and has a function of equalizing and controlling the temperature of the counter electrode 2 that is in contact.

  The soaking plate holding mechanism 11 holds the soaking plate 5 and the counter electrode 2 so as to be substantially parallel to the side surface (the right side in FIG. 2) of the film forming chamber 6. During film formation, the soaking plate 5, the counter electrode 2 and the substrate 8 are brought close to the discharge electrode 3.

FIG. 3 shows the load chamber 21. In this apparatus, a transparent conductive film (TCO film) 8a (see FIG. 6) having a thickness of 500 to 800 nm, which is mainly composed of a tin oxide film (SnO ₂ ), is formed in the chamber 21a of the load chamber 21. The substrate 8 is installed and heated by an IR heater 70 provided to face the substrate 8. The IR heater 70 preferably has a radiation beam radiation area slightly larger than the size of the substrate 8 so that the substrate 8 is heated to a uniform temperature distribution. In the chamber 21a, a substrate support frame 71 for supporting the substrate 8 carried in by a substrate transfer device (not shown) at a predetermined position, the IR heater 70, and a position opposite to the IR heater 70 with respect to the substrate 8. A black radiation plate 72 provided between the substrate support frame 71 and the substrate 8 is provided.

  As the IR heater 70, a readily available halogen type IR heater can be used, and the substrate 8 is heated by the emitted radiation. A part of the wavelength emitted from the IR heater 70 passes through the substrate 8 without being absorbed. The glass plate 8 b and the transparent conductive film (TCO film) 8 a of the substrate 8 have the following general characteristics with respect to the wavelength range of the radiation rays emitted by the IR heater 70.

Wavelengths less than 1.5 μm are transmitted through the transparent conductive film (TCO film) 8a and the glass plate 8b.
A part of the wavelength of 1.5 to 2.5 μm is absorbed by the transparent conductive film (TCO film) 8a, and the transparent conductive film (TCO film) 8a is heated. A part is not absorbed and passes through the glass plate 8b.
Wavelengths of 2.5 μm or less are transmitted through the glass plate 8b.
A part of the wavelength of 2.5 μm or more is absorbed by the glass plate 8b.
A part of the wavelength of 2.5 μm to 3.0 μm is absorbed by the transparent conductive film (TCO film) 8 a and the glass plate 8 b, and part of the wavelength is transmitted without being absorbed.
A wavelength of 3.0 μm or more is reflected by the transparent conductive film (TCO film) 8a.

  FIG. 4 shows the absorption coefficient of the glass plate. Most of the short wavelengths of 1.5 μm or less are transmitted without being absorbed by the glass plate and the TCO film. It can be seen that a long wavelength of 2.5 μm or more is easily absorbed by the glass plate.

FIG. 5 shows the absorptance and reflectance of a transparent conductive film (TCO film) mainly composed of SnO ₂ . Although the numerical value slightly varies depending on the doping rate and film thickness of fluorine or the like, reflection at the wavelength of 3.0 μm or more is often reflected by the transparent conductive film (TCO film). It can be seen that at a wavelength of 1.5 μm or more and 3.0 μm or less, reflection by the transparent conductive film (TCO film) is small and absorption is difficult.

Therefore, when the substrate 8 is heated by the IR heater 70 from the surface of the transparent conductive film (TCO film) 8a, a wavelength of 1.5 μm or more and 3.0 μm or less is effectively used for substrate heating. A wavelength of 2.5 μm or more and 3.0 μm or less is preferable because there is little reflection by the transparent conductive film (TCO film) 8a and absorption at the substrate 8 is high.
On the other hand, when the substrate 8 is heated by the IR heater 70 from the glass surface opposite to the transparent conductive film (TCO film) 8a surface, the wavelength of 1.5 μm or more is not limited by the wavelength of 3.0 μm or less. It can be used effectively for substrate heating. However, the substrate support frame 71 generates a temperature distribution on the substrate 8 and is not suitable for a structure in which a large substrate is heated to a uniform temperature distribution. For this reason, a new structure using the black radiation plate 72 is preferable.

  The black radiation plate 72 has a size that covers almost the entire substrate support frame 71, and the substrate 8 is placed between the black radiation plate 72 and the IR heater 70 as shown in FIG. 3. When the black radiation plate 72 is heated, infrared rays having a wavelength that is easily absorbed by the substrate 8 are emitted. In the present embodiment, heating is performed so as to emit infrared rays having a wavelength of at least 2.5 μm or more, preferably 3.0 μm or more, and having high energy on the short wavelength side. The black radiation plate 72 is preferably heated to 400 ° C. or more by the radiation light transmitted through the substrate 8. When the black radiation plate 72 is heated to about 400 ° C., radiation light mainly having a wavelength of about 4.0 μm is emitted to the substrate 8. As shown in FIG. Easy to be absorbed.

  The material of the black radiating plate 72 is, for example, a normal durable vacuum material such as SUS304, and an oxide film of about 1 μm is formed on the surface by using an anodic oxidation method or the like. Black having a radiation rate (for example, a radiation rate of 0.8 or more). The black radiation plate 72 is desirably degassed in a vacuum and stable even at a high temperature of about 500 ° C. The surface of the black radiation plate 72 is not limited to the anodic oxidation method, and the surface shape is fine so as to be less than the wavelength of the light source of the IR heater 70 You may make it the shape which provided the unevenness | corrugation, and may apply | coat a zirconia-type black ceramic material to a metal plate by thermal spraying, slurry coating, etc.

In the vacuum processing apparatus of the present embodiment configured as described above, when heating is performed by the IR heater 70, as shown in FIG.
When the wavelength of the radiation beam is 3.0 μm or more, specifically, 2.8 μm or more, it is reflected by the transparent conductive film (TCO film) 8a,
In 2.5-3.0 micrometers, a part is absorbed by the transparent conductive film (TCO film) 8a and the glass plate 8b, the transparent conductive film (TCO film) 8a and the glass plate 8b are heated, a part permeate | transmits,
When the thickness is 1.5 μm or less, the transparent conductive film (TCO film) 8a and the glass plate 8b are transmitted.
In 1.5-2.5 micrometers, a part is absorbed by the transparent conductive film (TCO film) 8a, the transparent conductive film (TCO film) 8a is heated, and a part is transparent conductive film (TCO film) 8a and a glass plate. 8b is transmitted.
The black radiation plate 72 is heated by a radiation beam having a wavelength of 1.5 to 3.0 μm partially transmitted through the substrate 8 and a wavelength of 1.5 μm or less transmitted most. Thereby, the black radiation plate 72 emits radiation mainly including far-infrared rays having a wavelength of at least 2.5 μm or more, preferably 2.8 μm or more, more preferably 3.0 μm or more, and the substrate 8 is heated from behind. .

Thus, the wavelength transmitted through the substrate 8 is converted into a long wavelength by the black radiation plate 72 at a low cost. That is, by converting to a wavelength that is easily absorbed by the glass plate 8b, the heating efficiency of the substrate 8 by the IR heater 70 is improved, the amount of heat that escapes to the chamber 21a is suppressed, and the amount of power input to the IR heater and the chamber wall surface (especially The running cost can be reduced by reducing the cooling water flow rate for cooling the portion sealed with an O-ring or the like.
In addition, it becomes possible to heat both sides of the substrate 8 without installing IR heaters on both sides of the substrate 8, and the temperature difference between the front and back sides of the substrate 8 can be reduced. The substrate 8 can be stably supported by the substrate support frame 71 without dropping off under the heat flux with high rapid heating. In particular, when the thickness of the substrate 8 is thick (for example, 4 mm for a thin film solar cell superstrate), the effect of preventing warping is significant.
As a result of the thermal analysis, it was confirmed that the contribution ratio of the input power of the IR heater 70 to the substrate heating was improved from 22% to 27%.
Even in a single glass substrate (only the glass plate 8b) in which the transparent conductive film (TCO film) 8a is not formed, heating with radiation light having an effective wavelength from the front and back sides of the substrate is performed. More preferable substrate heating is performed than the IR heater heating system without the plate 72.

[Second Embodiment]
In the case where the substrate 8 is heated by the IR heater 70 from the transparent conductive film (TCO film) 8a side in the conventional thin film manufacturing apparatus, 3.0 μm or more of the wavelength emitted from the IR heater 70 is not less than 3.0 μm. Membrane) It was found that the film was not effectively used because of the increased reflection at 8a. Therefore, in the present embodiment, the IR heater 70 has a peak emission wavelength at which the reflection by the transparent conductive film (TCO film) 8a is small. That is, the peak wavelength of the highest radiant intensity of the emitted radiation is set to 1.5 μm to 3 μm, preferably 2.8 μm. In order to increase the amount of absorption in the transparent conductive film (TCO film) 8a and the glass plate 8b, it is more preferably 2.5 μm or more and 2.8 μm or less. The emission peak wavelength can be controlled by changing the heating wire diameter or length of the IR heater 70. Increasing the heating wire diameter increases the wavelength, and decreasing it decreases the wavelength. Increasing the heating wire length increases the wavelength, and shortening it decreases the wavelength.
Since other configurations are the same as those of the first embodiment, a duplicate description is omitted.

  As a result, the proportion reflected by the transparent conductive film (TCO film) 8a is reduced, and the wavelength transmitted through the transparent conductive film (TCO film) 8a and the substrate 8 is longer by the black radiation plate 72 as in the first embodiment. Reflected to the wavelength and used effectively for substrate heating. As a result, it was confirmed that the substrate heating of the input power further improved from 22% to 36% as a result of thermal analysis. Needless to say, the peak wavelength of the emitted radiation can be appropriately changed in accordance with the characteristics and film thickness of the transparent conductive film (TCO film).

[Third Embodiment]
For each of the above embodiments, the thickness of the black radiation plate 72 may be limited as follows. Since other configurations are the same as those in the above embodiments, description thereof is omitted.

The amount of radiant heat transferred to the black radiation plate 72 is expressed by the following equation.
Q (heater → _{board) = A o F o ε o} ε s σ [(T o / 100) ^ 4- (T s / 100) ^ 4]
Q (black radiation plate → substrate) = A _b F _b ε _s ε _b σ [(T _b / 100) ^ 4- (T _s / 100) ^ 4]
A _o : IR heater area, A _s : substrate area, A _b : black radiation plate area F _o, F _s, F _b : form factor ε _o, ε _s, ε _b : emissivity σ: Stefan Boltzmann coefficient T _o : IR heater temperature, T _s : substrate temperature, T _b : black radiation plate temperature

Therefore, the amount of heat input to the substrate 8 increases as the temperature of the black radiation plate 72 increases, and high-speed heating is possible. The emissivity of the black radiation plate 72: epsilon _b is becomes larger as the temperature is high, which is advantageous for further heating the substrate.

After τ time, the black radiation plate temperature _Tb is
(T _b ′ −T _w ) / (T _o −T _w ) = Exp (−hA / (CM) × τ)
T _b ′: Unsteady black radiation plate temperature, T _o : IR heater temperature, T _w : Black radiation plate cooling side temperature (assuming chamber wall surface)
C: black radiant plate specific heat, M: black radiant plate mass, hA: heat transfer rate × heat transfer area = heat transfer rate

Therefore, in order to increase the black radiation plate temperature (T _b ′) quickly, not only the heat transfer rate: hA is increased, but also the reduction of the specific heat (C) and mass (M) of the black radiation plate 72 is effective. is there. For this reason, when using SUS304, the thinner one is desirable. For example, a foil plate having a thickness of 0.1 to 0.5 mm is used. Note that if SUS is changed to aluminum, the temperature rise can be increased by halving the CM, but there is no proof strength of about 500 ° C., and there is a use limit when the substrate heating temperature is increased.

  Thus, by setting the thickness of the black radiation plate 72 to be thin, the temperature of the black radiation plate rises quickly and the substrate 8 is also heated quickly.

[Fourth Embodiment]
As shown in FIG. 7, a reflection plate 73 is provided between the black radiation plate 72 and the substrate support frame 71. The reflection plate 73 is provided with a gap from the black radiation plate 72 through a washer or the like in order to reduce contact heat transfer with the black radiation plate 72 by fastening means (not shown). As the material of the reflector 73, a material having a high reflectance such as aluminum, an aluminum alloy (for example, A5052), a polished stainless material, or a nickel material is used. More preferably, an aluminum alloy foil or a nickel foil is preferable because there is no black change due to oxidation. Since other configurations are the same as those in the above embodiments, description thereof is omitted.

Accordingly, the heat escaping from the black radiation plate 72 to the chamber wall T _w is reflected by the reflecting plate 73, by heating the black radiation plate 72 to raise the temperature of the black radiation plate 72. Thereby, the emissivity is improved and the heat transfer to the substrate 8 is increased. In particular, when the temperature of the black radiating plate 72 is increased, it becomes possible to emit a shorter wavelength (high energy) radiation beam, and the heating contribution ratio of the substrate 8 is increased.
In addition, it is desirable that the reflection plate 73 is 0.2 or less, which is equivalent to the radiation rate of the SUS material having a smooth surface property so as to be lower than the radiation rate of the surrounding structure (for example, the SUS material). Further, in order to suppress the escape of heat to the chamber wall surface, two or more reflecting plates 73 may be provided in order to keep the surface temperature of the reflecting plate 73 high and reduce the heat transfer coefficient of the reflecting plate 73. . As a result, the above-described effects can be further effectively exhibited.

[Fifth Embodiment]
The structure which becomes the same board | plate material which has both the functions which the reflection plate 73 of the said 4th Embodiment has the both functions in which the side which faces the said board | substrate 8 is the black radiation plate 72, and the back side of the black radiation plate 72 is the said reflection plate. It is good. That is, the surface of one metal plate (SUS, etc.) on one side of the substrate 8 side is made a black radiation surface (black radiation plate 72) by anodizing or the like, and the surface opposite to the substrate 8 is polished. The reflection surface (reflection plate 73) is used. As a result, the number of parts is reduced, and in addition to the cost reduction of the part main body, the surface area of the additional parts is reduced.

[Sixth Embodiment]
As shown in FIG. 8, a reflection plate 74 is provided on at least a part of the wall surrounding the IR heater 70, the substrate 8, and the black radiation plate 72 on the inner wall surface of the chamber 21a. The reflection plate 74 is provided so as to reduce contact heat transfer with each inner wall surface of the chamber 21a by providing a gap on each inner wall surface of the chamber 21a, such as a vacuum exhaust port (not shown), a GV valve for transporting the substrate, and the like. It is provided at a position excluding the space. The reflector 74 can be made of the same material as the reflector 73 in the fourth embodiment. Since other configurations are the same as those in the above embodiments, description thereof is omitted.

As a result, the amount of heat escaping to the wall surface of the chamber 21a is reduced, and the temperature of the black radiation plate 72 can be raised. Thereby, the amount of heat transfer to the substrate 8 increases. As the temperature of the black radiation plate 72 rises, it becomes possible to emit radiation light on the short wavelength side with larger energy, heat absorption to the substrate 8 is increased, and the heating contribution rate is improved. In particular, the wavelength (2.8 μm or more) reflected by the transparent conductive film (TCO film) 8 a is reflected by the reflecting plate 74 so as to enter the black radiation plate 72. As a result, the substrate heating efficiency can be increased.
Further, as the radiation beam for heating the substrate 8, radiation beams from the black radiation plate 72 and the reflection plate 74 are used in addition to those directly reaching from the IR heater, so that the temperature distribution of the substrate 8 can be made more uniform. is there.

  In addition, when providing the reflective plate 73 in the back direction of the black radiation plate 72 as in the fourth embodiment, it is not necessary to provide the reflective plate 74 on the inner surface of the outer chamber 21a.

[Seventh Embodiment]
As shown in FIG. 9, the second black radiation plate 75 is provided behind the IR heater 70 (a position opposite to the substrate 8 with respect to the IR heater 70). A reflective plate 74 may be provided behind the IR heater 70, and a second black radiation plate 75 may be provided between the reflective plate and the IR heater 70 as a separate body, or the reflective plate 74. The heater side surface may be a black radiation surface. As a result, the amount of infrared rays entering the substrate 8 is made more uniform, resulting in a more uniform temperature distribution, and the substrate heating efficiency is improved. In addition to this, a black radiation plate may be provided on a surface (lateral side surface) extending in a direction intersecting the substrate surface of the IR heater 70. Since other configurations are the same as those in the above embodiments, description thereof is omitted.

  The radiation beam reflected by the second black radiation plate 75 is a long wavelength beam of 1.5 to 3 μm so that the substrate 8 can be heated from the whole. Thereby, the heating efficiency of the substrate 8 can be improved and the temperature distribution of the substrate can be made uniform.

It is a schematic block diagram of a thin film manufacturing apparatus. It is sectional drawing of the film forming chamber with which the same thin film manufacturing apparatus is provided. It is a perspective view of the load chamber with which the said thin film manufacturing apparatus is provided. It is the figure which showed the absorption coefficient of the board | substrate. It is the figure which showed the absorptance and reflectance of the transparent conductive film (TCO film). It is the schematic diagram which showed the wavelength which a board | substrate permeate | transmits or absorbs. It is the perspective view which showed the load lock chamber of the thin film manufacturing apparatus which concerns on 4th Embodiment of this invention. It is the perspective view which showed the load lock chamber of the thin film manufacturing apparatus which concerns on 6th Embodiment of this invention. It is the perspective view which showed the load lock chamber of the thin film manufacturing apparatus which concerns on 7th Embodiment of this invention.

Explanation of symbols

1 Thin film production equipment (vacuum processing equipment)
8 Substrate 8a Transparent conductive film (TCO film)
8b Glass plate 21 Load chamber 21a Chamber 70 IR heater 71 Substrate support frame 72 Black radiation plate 73 Reflection plate 74 Reflection plate 75 Second black radiation plate

Claims (8)

A chamber for processing the glass substrate under a reduced pressure from atmospheric pressure; a heater for heating the glass substrate in the chamber; and a black radiation plate provided on the opposite side of the heater from the glass substrate; With
The black radiation plate is a foil plate provided apart from the wall surface of the chamber, and is heated mainly by the light transmitted through the glass substrate among the radiation rays emitted from the heater. A vacuum processing apparatus that emits radiated light and heats the glass substrate from a side opposite to the heater.   A transparent conductive film is formed on at least a part of the surface of the glass substrate, and the peak wavelength of the highest radiant intensity in the infrared region among the radiation rays emitted from the heater is 80% or more by the transparent conductive film. The vacuum processing apparatus according to claim 1, which has a wavelength that is not reflected.   The vacuum processing apparatus according to claim 2, wherein the peak wavelength is 1.5 μm or more and 3.0 μm or less.   The vacuum processing apparatus in any one of Claim 1 to 3 with which the reflecting plate is provided in the position on the opposite side to the said glass substrate with respect to the said black radiation board.   The vacuum processing apparatus according to claim 4, comprising the same plate member having both functions, wherein the side facing the substrate is the black radiation plate, and the back side of the black radiation plate is the reflection plate.   The vacuum processing apparatus according to any one of claims 1 to 5, wherein a reflection plate is provided on at least a part of a range surrounding the heater, the glass substrate, and the black radiation plate on the inner wall surface of the chamber.   The vacuum processing apparatus in any one of Claim 1 to 6 with which the 2nd black radiation board was provided in the position on the opposite side to the said glass substrate with respect to the said heater. A heater provided at a position facing the glass substrate in the chamber depressurized from the atmospheric pressure emits a radiation beam, and the glass substrate is heated by the radiation beam,
The black radiation plate provided on the opposite side to the heater with respect to the glass substrate and spaced from the wall surface of the chamber is heated by the light transmitted through the glass substrate among the radiation rays, and the heated black radiation plate Emits radiant light mainly composed of far infrared rays, and heats the glass substrate from the opposite side of the heater.

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