Wafer loading and unloading chamber and vertical furnace

Abstract

The invention relates to the technical field of vertical furnaces, in particular to a wafer loading and unloading chamber and a vertical furnace, which comprise a wafer boat, a filter, a heat exchanger, a return pipe, a fan and a heat energy absorption part, and in the process that the wafer descends into the wafer loading and unloading chamber along with the wafer boat, the low-temperature nitrogen flows out from the nitrogen outflow hole of the filter and flows to the wafer boat and the wafer. And carrying out cooling treatment on the wafer boat and the wafer by means of low-temperature nitrogen. And then the high-temperature nitrogen flows into the heat exchanger through the nitrogen recovery hole for cooling treatment. And the cooled nitrogen flows to the filter again through the return pipe under the action of the fan to be reused. By additionally arranging the heat energy absorption part, the heat energy absorption part can quickly absorb heat energy from the wafer boat, the wafer and the environment in the wafer loading and unloading chamber, so that the cooling rate of the wafer boat and the wafer is improved, the rising amplitude of the environment temperature in the wafer loading and unloading chamber is reduced, and the service life of other equipment in the wafer loading and unloading chamber is prolonged; and potential safety hazards are reduced.

Description

Technical Field

[0001] The invention relates to the technical field of vertical furnaces, and in particular to a wafer loading and unloading chamber and a vertical furnace. Background Art

[0002] When the wafer is just lowered into the wafer loading and unloading chamber with the wafer boat, the temperature can reach 600℃-650℃. A large amount of heat is radiated into the wafer loading and unloading chamber, causing the temperature in the wafer loading and unloading chamber to increase sharply in a short period of time, accelerating the aging of other equipment in the wafer loading and unloading chamber.

[0003] Therefore, how to extend the service life of other equipment in the wafer loading and unloading chamber has become a technical problem that needs to be solved urgently by technical personnel in this field. Summary of the invention

[0004] The invention provides a wafer loading and unloading chamber, which is used to solve the problem of how to prolong the service life of other equipment in the wafer loading and unloading chamber.

[0005] In one aspect, the present invention provides a wafer loading and unloading chamber, comprising: A wafer boat is arranged in the wafer loading and unloading chamber and is used to carry wafers; A filter is arranged on one side of the wafer boat; a nitrogen outflow hole is formed on the filter, and nitrogen is blown toward the wafer boat through the nitrogen outflow hole; The heat exchanger is arranged on a side of the crystal boat away from the filter; a nitrogen recovery hole is formed on the heat exchanger; A reflux pipe is arranged at the bottom of the wafer loading and unloading chamber and is connected to the filter and the heat exchanger respectively; A fan is installed in the return pipe; The heat energy absorption part is arranged on a side of the wafer boat away from the filter and is used for absorbing the heat energy in the wafer loading and unloading chamber.

[0006] In some of the embodiments, the thermal energy absorber is capable of absorbing thermal radiation with a wavelength of 2.5 μm-3.5 μm.

[0007] In some embodiments, the heat energy absorbing portion is a heat absorbing plate, and a heat absorbing layer is formed on the surface through an oxidation process.

[0008] In some of the embodiments, the area of ​​the heat energy absorbing portion is larger than the area of ​​the cross section of the wafer boat along the vertical direction.

[0009] In some embodiments, it also includes: The heat energy converging part is arranged in the wafer loading and unloading chamber and can make the heat radiation converge on the heat energy absorbing part.

[0010] In some embodiments, the heat concentrating portion comprises: The first reflection plate is arranged on a common side of the crystal boat and the filter; the first reflection plate is an arc-shaped structure, and the concave surface faces the heat energy absorption part.

[0011] In some embodiments, the heat energy concentrating unit further comprises: There are three second reflective plates, which are respectively arranged on three adjacent sides of the wafer boat; each second reflective plate is a flat plate structure.

[0012] In some embodiments, it also includes: The lifting mechanism is connected to the bottom end of the crystal boat and is used to drive the crystal boat to move up and down.

[0013] In some embodiments, it also includes: The rotating mechanism is installed on the lifting mechanism and connected to the crystal boat, and can drive the crystal boat to rotate around its own axis.

[0014] On the other hand, the present invention further provides a vertical furnace, comprising a furnace tube and a wafer loading and unloading chamber provided in any embodiment; The furnace tube is arranged above the wafer loading and unloading chamber.

[0015] The beneficial effects of the present invention are as follows: The wafer loading and unloading chamber of the present invention is provided with a wafer boat, a filter, a heat exchanger, a reflux pipe, a fan and a heat energy absorption part. When the wafer is lowered into the wafer loading and unloading chamber along with the wafer boat, low-temperature nitrogen flows out from the nitrogen outflow hole of the filter and flows to the wafer boat and the wafer. The wafer boat and the wafer are cooled by means of low-temperature nitrogen. Afterwards, the high-temperature nitrogen flows into the heat exchanger through the nitrogen recovery hole, and the high-temperature nitrogen is cooled by the heat exchanger. Under the action of the fan, the nitrogen that has been cooled flows to the filter again through the reflux pipe and is reused. By adding a heat energy absorption part, the heat energy absorption part can quickly absorb the heat energy from the wafer boat, the wafer and the environment in the wafer loading and unloading chamber, which not only improves the cooling rate of the wafer boat and the wafer, but also reduces the temperature rise of the environment in the wafer loading and unloading chamber, which is beneficial to extend the service life of other equipment in the wafer loading and unloading chamber and reduces safety hazards. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a top view of a wafer loading and unloading chamber of the present invention; Figure 2 yes Figure 1 A cross-sectional view of the wafer loading and unloading chamber along AA is shown; Figure 3 It is a structural schematic diagram of a vertical furnace of the present invention.

[0017] In the accompanying drawings, 110, crystal boat; 111, bottom plate; 112, support rod; 113, top plate; 120, filter; 130, heat exchanger; 140, return pipe; 150, fan; 160, heat energy absorption part; 171, first reflection plate; 172, second reflection plate; 180, lifting mechanism; 181, support column; 182, lifting platform; 190, rotating mechanism; 191, driving motor; 192, turntable; 193, thermal insulation; 200, furnace tube. DETAILED DESCRIPTION

[0018] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] As described in the background technology, when the wafer is just lowered into the wafer loading and unloading chamber with the wafer boat, the temperature can reach 600℃-650℃, and a large amount of heat is radiated into the wafer loading and unloading chamber, causing the temperature in the wafer loading and unloading chamber to rise sharply in a short period of time, accelerating the aging of other equipment in the wafer loading and unloading chamber. Therefore, how to extend the service life of other equipment in the wafer loading and unloading chamber has become a technical problem that needs to be solved urgently by those skilled in the art.

[0020] To solve the above problems, refer to Figure 1 and Figure 2 On the one hand, the present invention provides a wafer loading and unloading chamber, including a wafer boat 110, a filter 120, a heat exchanger 130, a reflux pipe 140, a fan 150 and a heat energy absorber 160. The wafer boat 110 is arranged in the wafer loading and unloading chamber. The wafer boat 110 is used to carry wafers. The filter 120 is arranged on one side of the wafer boat 110, and is used to filter nitrogen to prevent the nitrogen blown to the wafer boat 110 from being mixed with foreign matter. A nitrogen outflow hole is formed on the filter 120, and nitrogen is blown to the wafer boat 110 through the nitrogen outflow hole. The heat exchanger 130 is arranged on the side of the wafer boat 110 away from the filter 120. A nitrogen recovery hole for recovering nitrogen is formed on the heat exchanger 130. The heat exchanger 130 is used to cool the nitrogen. The reflux pipe 140 is arranged at the bottom of the wafer loading and unloading chamber, and is connected to the filter 120 and the heat exchanger 130 respectively. The fan 150 is installed in the reflux pipe 140 to provide assistance to the flow of nitrogen, so as to make the nitrogen flow faster, so as to increase the cooling rate of the wafer boat 110, the wafers and the environment in the wafer loading and unloading chamber. The heat energy absorber 160 is arranged on the side of the wafer boat 110 away from the filter 120, and is used to absorb the heat energy in the wafer loading and unloading chamber.

[0021] The working process and principle of the wafer loading and unloading chamber are as follows: When the wafer is lowered into the wafer loading and unloading chamber along with the wafer boat 110, Figure 2 The direction of the middle arrow is the flow direction of nitrogen. The low-temperature nitrogen flows out from the nitrogen outflow hole of the filter 120 and flows to the wafer boat 110 and the wafers. The wafer boat 110 and the wafers are cooled with the help of low-temperature nitrogen. After that, the high-temperature nitrogen flows into the heat exchanger 130 through the nitrogen recovery hole, and the heat exchanger 130 cools the high-temperature nitrogen. Under the action of the fan 150, the nitrogen that has been cooled flows to the filter 120 again through the return pipe 140 and is reused. It should be noted that nitrogen has a small heat capacity and absorbs very little heat. The wafers and wafer boat 110 in a high-temperature state will still radiate a large amount of heat into the wafer loading and unloading chamber. Therefore, a heat energy absorption part 160 is added. The heat energy absorption part 160 can quickly absorb heat energy from the wafer boat 110, wafers and the environment inside the wafer loading and unloading chamber, which not only improves the cooling rate of the wafer boat 110 and the wafers, but also reduces the increase in the ambient temperature inside the wafer loading and unloading chamber, which is beneficial to extend the service life of other equipment in the wafer loading and unloading chamber and reduce safety hazards.

[0022] It should be noted that the heat energy absorption part 160 can absorb heat radiation with a wavelength of 2.5 μm-3.5 μm, so as to reduce the increase in the environment in the wafer loading and unloading chamber.

[0023] In some embodiments, the heat absorbing portion 160 is a heat absorbing plate, and a heat absorbing layer is formed on the surface through an oxidation process. The heat absorbing plate is made of aluminum, and an aluminum oxide layer is formed on the surface of the aluminum plate through a black anodizing process. As a heat absorbing layer, the aluminum oxide layer can quickly and effectively absorb thermal radiation with a wavelength of 2.5 μm-3.5 μm.

[0024] In some other embodiments, the heat energy absorbing part 160 may be a box storing water, which can absorb a large amount of heat in the environment due to the large heat capacity of water.

[0025] Specifically, in the exemplary embodiment, the area of ​​the heat energy absorbing portion 160 is larger than the area of ​​the vertical cross section of the wafer boat 110 to ensure the heat absorption effect and heat absorption rate. The front side of the heat energy absorbing portion 160 can be extended to the front side of the wafer loading and unloading chamber, the rear side can be extended to the rear side of the wafer loading and unloading chamber, the top can be extended to the top of the wafer loading and unloading chamber, and the bottom can be extended to the bottom of the wafer loading and unloading chamber, so that the area of ​​the heat energy absorbing portion 160 is larger than the area of ​​the vertical cross section of the wafer boat 110, thereby ensuring the heat absorption effect and heat absorption rate.

[0026] Specifically, in the example, Figure 1As shown, the wafer loading and unloading chamber also includes a heat energy converging portion. The heat energy converging portion is arranged in the wafer loading and unloading chamber, which can direct heat radiation in a certain direction to the heat energy absorbing portion 160, reduce the degree of heat diffuse reflection, and help to increase the cooling rate of the wafer boat 110, the wafers and the ambient temperature.

[0027] In some embodiments, the heat energy convergence portion only includes the first reflector 171. The first reflector 171 is disposed on a common side of the wafer boat 110 and the filter 120. It should be noted that the space available for secondary development and utilization in the wafer loading and unloading chamber is very limited, so the position of the first reflector 171 cannot be arranged arbitrarily. The first reflector 171 is an arc-shaped structure, with the concave surface facing the heat energy absorption portion 160, which is conducive to the heat radiation being gathered on the heat energy absorption portion 160.

[0028] In other embodiments, the heat energy converging portion includes a first reflective plate 171 and three second reflective plates 172. The first reflective plate 171 is disposed on a common side of the wafer boat 110 and the filter 120. The first reflective plate 171 is an arc-shaped structure, with the concave surface facing the heat energy absorbing portion 160. The three second reflective plates 172 are respectively disposed on three adjacent sides of the wafer boat 110, and each second reflective plate 172 is a flat plate structure. Figure 1 The direction of the middle arrow is the heat reflection direction, which is more conducive to the heat radiation being collected on the heat energy absorption part 160. Since the three second reflection plates 172 have a reflective effect, the heat in the wafer loading and unloading chamber is prevented from being transferred to other equipment such as guide rails, lead screws, cables and air pipes outside the three second reflection plates 172, thereby extending the service life of other equipment.

[0029] Specifically, in the example, Figure 2 As shown, the wafer loading and unloading chamber further includes a lifting mechanism 180 and a rotating mechanism 190. The lifting mechanism 180 is connected to the bottom end of the wafer boat 110, and is used to drive the wafer boat 110 to move up and down, so as to transfer the wafer boat 110 and the wafers into the furnace tube 200 or into the wafer loading and unloading chamber. The rotating mechanism 190 is installed on the lifting mechanism 180 and connected to the wafer boat 110. After the wafer boat 110 and the wafers are transferred into the furnace tube 200, the rotating mechanism 190 can drive the wafer boat 110 to rotate around its own axis.

[0030] Preferably, the lifting mechanism 180 includes a support column 181 and a lifting platform 182. The lifting platform 182 is installed on the support column 181 so as to be movable up and down. The rotating mechanism 190 includes a driving motor 191, a turntable 192 and a heat insulating member 193. The driving motor 191 is installed on the lifting platform 182. The turntable 192 is rotatably arranged above the lifting platform 182 around its own axis, and the middle part of the bottom end is fixedly connected to the driving motor 191. The heat insulating member 193 is installed on the top of the turntable 192 to play a heat insulating role. The wafer boat 110 includes a bottom plate 111, three support rods 112 and a top plate 113. The bottom plate 111 is installed on the top surface of the heat insulating member 193. Each support rod 112 is vertically arranged, and the bottom end is fixedly connected to the bottom plate 111. The top plate 113 is fixedly connected to the top of each support rod 112. Each support rod 112 is evenly distributed with a plurality of wafer support blocks along the axial direction. The wafer support blocks of each layer are used to support the wafers on that layer. The driving motor 191 can drive the turntable 192 and the heat insulating member 193 to rotate, thereby driving the wafer boat 110 and the wafers to rotate.

[0031] Preferably, the drive motor 191 may be a servo motor with high control accuracy or a stepper motor with low manufacturing cost.

[0032] Preferably, the thermal insulation member 193 includes a plurality of thermal insulation sheets stacked in sequence from top to bottom. Each layer of thermal insulation sheets is connected by a connecting member. Since the wafer boat 110 is located in the furnace tube 200 when performing processes such as depositing a film layer structure or annealing, and the temperature in the furnace tube 200 is very high, the thermal insulation member 193 is used to insulate the bottom of the wafer boat 110. On the one hand, it can prevent the heat of the wafer boat 110 from being transferred to the lifting platform 182; on the other hand, it can prevent the temperature at the bottom of the wafer boat 110 from being lower than the temperature at the top, which is conducive to keeping the temperature at the top and bottom of the wafer boat 110 consistent, so that the wafers carried at various positions of the wafer boat 110 are heated evenly.

[0033] Preferably, the heat insulating member 193 may be a transparent, translucent or non-transparent structure, and the material may be quartz or silicon nitride.

[0034] Preferably, the wafer boat 110 may be a transparent, translucent or non-transparent structure, and the material may be quartz or silicon nitride.

[0035] Preferably, the heat exchanger 130 is a fin-type heat exchanger to ensure that the high-temperature nitrogen can be cooled quickly.

[0036] Reference Figure 3 On the other hand, the present invention provides a vertical furnace, including a furnace tube 200 and a wafer loading and unloading chamber provided in any embodiment. The furnace tube 200 is arranged above the wafer loading and unloading chamber. A wafer boat 110 entry and exit is formed at the bottom of the furnace tube 200. The furnace tube 200 is used to heat the wafer boat 110 and the wafer.

[0037] In the process of the wafers descending from the furnace tube 200 to the wafer loading and unloading chamber along with the wafer boat 110, low-temperature nitrogen flows out from the nitrogen outflow hole of the filter 120 and flows to the wafer boat 110 and the wafers. The wafer boat 110 and the wafers are cooled with the help of low-temperature nitrogen. Afterwards, the high-temperature nitrogen flows into the heat exchanger 130 through the nitrogen recovery hole, and the heat exchanger 130 cools the high-temperature nitrogen. Under the action of the fan 150, the nitrogen that has been cooled flows to the filter 120 again through the return pipe 140 and is reused. It should be noted that nitrogen has a small heat capacity and absorbs very little heat. The wafers and the wafer boat 110 in a high-temperature state will still radiate a large amount of heat into the wafer loading and unloading chamber. Therefore, a heat energy absorption part 160 is added. The heat energy absorption part 160 can quickly absorb heat energy from the wafer boat 110, wafers and the environment inside the wafer loading and unloading chamber, which not only improves the cooling rate of the wafer boat 110 and the wafers, but also reduces the increase in the ambient temperature inside the wafer loading and unloading chamber, which is beneficial to extend the service life of other equipment in the wafer loading and unloading chamber and reduce safety hazards.

[0038] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0039] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0040] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] In the present invention, the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0042] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A wafer loading and unloading chamber, characterized in that: include: A wafer boat, arranged in the wafer loading and unloading chamber, for carrying wafers; A filter is disposed on one side of the wafer boat; a nitrogen outflow hole is formed on the filter, and nitrogen is blown toward the wafer boat through the nitrogen outflow hole; A heat exchanger is arranged on a side of the crystal boat away from the filter; a nitrogen recovery hole is formed on the heat exchanger; A reflux pipe, disposed at the bottom of the wafer loading and unloading chamber, and connected to the filter and the heat exchanger respectively; A fan is installed in the return pipe; The heat energy absorption part is arranged on a side of the wafer boat away from the filter and is used for absorbing the heat energy in the wafer loading and unloading chamber.

2. The wafer loading and unloading chamber according to claim 1, characterized in that: The heat energy absorbing portion can absorb heat radiation with a wavelength of 2.5 μm-3.5 μm.

3. The wafer loading and unloading chamber according to claim 1, characterized in that: The heat energy absorbing part is a heat absorbing plate, and a heat absorbing layer is formed on the surface through an oxidation process.

4. The wafer handling chamber according to claim 1, characterized in that: The area of ​​the heat energy absorbing portion is larger than the area of ​​the cross section of the wafer boat along the vertical direction.

5. The wafer loading and unloading chamber according to any one of claims 1 to 4, characterized in that: Also includes: The heat energy converging part is arranged in the wafer loading and unloading chamber and can make the heat radiation converge on the heat energy absorbing part.

6. The wafer loading and unloading chamber according to claim 5, characterized in that: The heat energy converging part comprises: The first reflector is arranged on a common side of the crystal boat and the filter; the first reflector is an arc-shaped structure, and a concave surface faces the heat energy absorbing part.

7. The wafer loading and unloading chamber according to claim 6, characterized in that: The heat energy converging portion further comprises: There are three second reflective plates, which are respectively arranged on three adjacent sides of the wafer boat; each of the second reflective plates is a flat plate structure.

8. The wafer loading and unloading chamber according to any one of claims 1 to 4, characterized in that: Also includes: The lifting mechanism is connected to the bottom end of the wafer boat and is used to drive the wafer boat to move up and down.

9. The wafer loading and unloading chamber according to claim 8, characterized in that: Also includes: The rotating mechanism is installed on the lifting mechanism and connected to the wafer boat, and can drive the wafer boat to rotate around its own axis.

10. A vertical furnace comprising a furnace tube and a wafer loading and unloading chamber according to any one of claims 1 to 9; The furnace tube is arranged above the wafer loading and unloading chamber.

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