CN111520999A

CN111520999A - Vertical furnace equipment

Info

Publication number: CN111520999A
Application number: CN202010290596.9A
Authority: CN
Inventors: 杨慧萍; 杨帅
Original assignee: Beijing Naura Microelectronics Equipment Co Ltd
Current assignee: Beijing Naura Microelectronics Equipment Co Ltd
Priority date: 2020-04-14
Filing date: 2020-04-14
Publication date: 2020-08-11
Anticipated expiration: 2040-04-14
Also published as: CN111520999B

Abstract

The invention discloses a vertical furnace device, comprising: furnace body, be located the technology pipe in the furnace body, be located the wafer boat in the technology pipe and set up in the technology door of the bottom of technology pipe, still including being located the heat preservation device in the technology pipe, the heat preservation device includes: the first heat preservation area comprises a plurality of first heat preservation inserting pieces which are arranged at intervals along the axial direction of the process tube; the second heat preservation area is arranged above the first heat preservation area and comprises a plurality of second heat preservation inserting pieces which are arranged at intervals along the axial direction of the process pipe; the cover plate is used for separating the first heat preservation area from the second heat preservation area; the annular cover is arranged above the cover plate and surrounds the peripheries of the second heat-preservation inserting pieces, and the top surface of the annular cover is used for supporting the wafer boat; the heat preservation base assembly is located above the process door and arranged in the first heat preservation area and used for supporting the second heat preservation inserting pieces, and the heat preservation base assembly is fixedly connected with the cover plate.

Description

Vertical furnace equipment

Technical Field

The invention relates to the field of semiconductor equipment, in particular to vertical furnace equipment.

Background

The vertical furnace is a processing device for processing semiconductor silicon wafers. The silicon wafer processing technology is a very precise technology, and the temperature is a very important index in the silicon wafer processing technology, and the index directly influences the thickness and uniformity of the silicon wafer film thickness. The process temperature of the prior high-temperature vertical furnace can reach 1200 ℃. In order to ensure the constant temperature of the wafer position in the chamber, an effective heat insulation structure is needed to ensure the uniform upper and lower temperature in the wafer process. On the other hand, generally, a sealing component is disposed in the bottom structure of the chamber, and the excessive temperature may cause the failure of the sealing component, destroy the sealing environment of the chamber, and further cause the quality of the wafer to be damaged.

In order to ensure the stability of the temperature in the vertical furnace thermal reaction tube and improve the heat preservation effect, a heat preservation device is arranged in the vertical furnace. The heat preservation device is positioned at the lower part of the furnace body thermal reaction tube and is used for supporting the quartz boat and providing heat preservation effect. Meanwhile, the heat preservation device structure can simultaneously ensure the process temperature at the position of the wafer in the cavity and the low temperature at the bottom by reducing the heat transferred from the upper part to the bottom of the cavity.

The existing heat preservation device is a full-quartz heat preservation barrel, quartz heat preservation barrel inserts cannot be directly used at high temperature of 1200 ℃, and quartz materials have large deformation or other defects at high temperature, so that reliable support of a wafer boat at high temperature cannot be met.

Therefore, a heat preservation device is expected, which has good heat resistance and thermal stability, ensures the heat preservation effect of the chamber, can ensure the low temperature at the bottom of the process tube, enables the sealing element to realize effective sealing, and can provide reliable support for the boat.

Disclosure of Invention

The invention aims to provide vertical furnace equipment, which solves the problems that the existing heat preservation device cannot resist high temperature and a sealing part fails due to overhigh temperature at the bottom of a process pipe.

To achieve the above object, the present invention provides a vertical furnace apparatus comprising: the furnace body, be located the technology pipe in the furnace body, be located the boat in the technology pipe and set up in the technology door of the bottom of technology pipe, its characterized in that still includes to be located the intraductal heat preservation device of technology, heat preservation device includes:

the first heat-preservation area comprises a plurality of first heat-preservation inserting pieces which are axially arranged along the process tube at intervals;

the second heat preservation area is arranged above the first heat preservation area and comprises a plurality of second heat preservation inserting pieces which are axially arranged along the process pipe at intervals;

the cover plate is used for separating the first heat preservation area from the second heat preservation area;

the annular cover is arranged above the cover plate and surrounds the peripheries of the second heat-preservation inserting pieces, and the top surface of the annular cover is used for supporting the wafer boat;

the heat preservation base subassembly is located technology door top just set up in the first heat preservation district, be used for supporting a plurality of the second inserted sheet that keeps warm, just the heat preservation base subassembly with apron fixed connection.

Preferably, the cover plate is provided with a first locking structure, the annular cover is provided with a second locking structure, and the first locking structure and the second locking structure are matched with each other to realize the connection between the cover plate and the annular cover.

As a preferred scheme, the first locking structure is at least two positioning protrusions or at least two positioning grooves distributed along the circumferential direction of the cover plate, the second locking structure is a matching groove or a matching protrusion corresponding to and matched with the positioning protrusions or the positioning grooves, and the annular cover is locked and unlocked with the cover plate in a rotating manner.

Preferably, the top surface of the annular cover is an annular plane.

Preferably, the annular cover is made of silicon carbide; and/or

It is a plurality of the material of second heat preservation inserted sheet is carborundum, perhaps, partly the material of second heat preservation inserted sheet is carborundum, another part the material of second heat preservation inserted sheet is quartz.

As preferred scheme, heat preservation base subassembly include the bottom plate with set up in the bracing piece of bottom plate top, the bracing piece runs through first heat preservation inserted sheet is in order to fix first heat preservation inserted sheet, the top of bracing piece with apron fixed connection.

Preferably, the cover plate and the heat-preservation base component are both made of quartz materials.

As the preferred scheme, first heat preservation inserted sheet with the second keeps warm the inserted sheet and is the disc form, the diameter of first heat preservation inserted sheet is greater than the diameter of second heat preservation inserted sheet.

Preferably, the number of the supporting rods is four, and the four supporting rods are uniformly distributed on the bottom plate.

Preferably, the wafer boat and the annular cover are connected through silicon carbide screws.

The invention has the beneficial effects that:

the heat preservation device is integrally divided into a first heat preservation area (positioned below) and a second heat preservation area (positioned above), a high-temperature-resistant annular cover is arranged on the periphery of the second heat preservation area, the annular cover covers the bottommost part of a furnace body temperature area, the high-temperature part of a cavity is ensured to be in the range of the annular cover, the temperature of the upper half part of the second heat preservation area is almost consistent with the process temperature, so that the uniformity of the process area temperature is ensured, the second heat preservation area realizes the transition from the process area temperature to the temperature which can be borne by the first heat preservation area, the heat is reduced from the cavity to the bottom, so that the temperature of the bottom of the cavity is reduced, the sealing element is prevented from losing efficacy at high temperature, and the sealing part.

Furthermore, the second heat-preservation inserting piece is made of a high-temperature-resistant material, and the second heat-preservation inserting piece which is at least located in a high-temperature area close to the process temperature on the upper portion of the second heat-preservation area is made of the high-temperature-resistant material, so that a better heat-preservation effect is achieved.

Furthermore, the top surface of the annular cover is a plane, and the annular cover cannot deform at high temperature, so that stable support can be provided for the wafer boat arranged above the annular cover.

Furthermore, the annular cover and the cover plate are assembled and disassembled in a rotating mode, the operation is simple, and the stability between the annular cover and the cover plate can be ensured.

The present invention has other features and advantages which will be apparent from or are set forth in detail in the accompanying drawings and the following detailed description, which are incorporated herein, and which together serve to explain certain principles of the invention.

Drawings

The above and other objects, features and advantages of the present invention will become more apparent by describing in more detail exemplary embodiments thereof with reference to the attached drawings, in which like reference numerals generally represent like parts.

Fig. 1 shows a schematic structural view of a vertical furnace installation according to an embodiment of the invention.

Fig. 2 is a schematic structural view showing a temperature keeping device in a vertical furnace apparatus according to an embodiment of the present invention.

Fig. 3 is an exploded view schematically showing a temperature maintaining device in a vertical furnace apparatus according to an embodiment of the present invention.

FIG. 4 illustrates a top view of a cover plate according to an embodiment of the present invention.

Fig. 5 shows a top view of a first insulating insert according to an embodiment of the invention.

FIG. 6 illustrates a top view of an annular shroud according to an embodiment of the present invention.

Fig. 7 and 8 show schematic views of a snap structure of the ring cover according to an embodiment of the present invention.

Description of reference numerals:

1, a furnace body; 2-a process tube; 3-a wafer boat; 4, wafer; 5-a heat preservation device; 6-a process door; 5-1 annular cover; 5-2 cover plates; 5-3, a first heat preservation insert; 5-4 second heat preservation inserting pieces; 5-5 heat-insulating base component; 5-51 bottom plates; 5-52 support rods; 5-6 quartz screws; 7, a silicon carbide screw; 8-1 a first L-shaped positioning tab; 8-2 second L-shaped positioning bumps; 9-1 a first mating recess; 9-2 second mating grooves; 10-a first temperature-holding zone; 11-second holding section.

Detailed Description

The invention will be described in more detail below with reference to the accompanying drawings. While the preferred embodiments of the present invention are shown in the drawings, it should be understood that the present invention may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

A vertical furnace apparatus according to an embodiment of the present invention is provided, and fig. 1 is a schematic structural view illustrating a vertical furnace apparatus according to an embodiment of the present invention. Fig. 2 shows a schematic structural view of an insulation apparatus according to an embodiment of the present invention. Fig. 3 shows an exploded view of a thermal insulation device according to an embodiment of the present invention. Referring to fig. 1, 2 and 3, the vertical furnace apparatus includes:

furnace body 1, be located furnace body 1 in the technology pipe 2, be located the brilliant boat 3 of technology pipe 2 and set up in the technology door 6 of the bottom of technology pipe 2, still including being located the heat preservation device of technology pipe 2, the heat preservation device includes:

the first heat preservation area 10 is formed by a plurality of first heat preservation inserting pieces 5-3 which are arranged along the axial direction of the process tube at intervals;

the second heat preservation area 11 is arranged above the first heat preservation area 10, and the second heat preservation area 11 comprises a plurality of second heat preservation inserting pieces 5-4 which are arranged at intervals along the axial direction of the process pipe;

a cover plate 5-2 separating the first heat preservation area 10 and the second heat preservation area 11;

the annular cover 5-1 is arranged above the cover plate 5-2 and surrounds the peripheries of the second heat-preservation inserting pieces 5-4, and the top surface of the annular cover 5-1 is used for supporting the wafer boat 3;

and the heat-insulation base component is positioned above the process door 6, arranged in the first heat-insulation area 10 and used for supporting the plurality of second heat-insulation inserting pieces 5-4, and fixedly connected with the cover plate 5-2.

Specifically, the process temperature of the vertical furnace equipment in the embodiment can reach 1200 ℃. The furnace body 1 is a heating part and is positioned on the outermost layer, and the top of the heat preservation device 5 is used for supporting the wafer boat 3. The heat preservation device 5 is placed on the process door 6 through the heat preservation base assembly, and the heat preservation device 5 achieves the heat preservation effect by preventing the heat of the cavity from losing from the bottom and effectively ensures that the temperature of the bottom is in the bearable range of the sealing element. The heat-preservation base component 5-5 comprises a bottom plate 5-51 and a supporting rod 5-52 arranged above the bottom plate 5-51, the top end of the supporting rod 5-52 extends to the lower surface of the cover plate 5-2, and the end part of the supporting rod 5-52 is connected with the cover plate 5-2. The lower surface of the bottom plate 5-51 is fixed on a process door 6 of the vertical furnace equipment, and the support rod 5-52 is fixed on the upper surface of the bottom plate 5-51 and is used for supporting the cover plate 5-2 and fixing the first heat-preservation inserting piece 5-3. The first heat-preservation inserting pieces 5-3 are arranged at intervals along the axial direction of the process tube. In this embodiment, there are 4 support rods 5-52 circumferentially distributed along the edge of the bottom plate 5-51. In other embodiments, the number of support bars 5-52 may be 3, 5, etc. distributed circumferentially along the edge of the base plate, preferably evenly distributed. Of course, the number of the support rods 5-52 may be 1, and the support rods are positioned at the center of the bottom plates 5-51. The top end of the support rod 5-52 extends to the lower surface of the cover plate 5-2 and is connected with the cover plate 5-2.

Referring to fig. 3 and 4, fig. 4 shows a top view of a cover plate according to an embodiment of the present invention. The cover plate 5-2 is in a circular plate shape, in the embodiment, the cover plate 5-2 and the support rod are made of quartz, and the cover plate 5-2 is connected with the support rod through a quartz screw 5-6. In this embodiment, the quantity of bracing piece is 4, and the corresponding 4 screw holes that are equipped with on the apron.

The supporting rod is used for supporting the cover plate 5-2 on one hand and fixing the first heat preservation inserting piece 5-3 on the other hand. Referring to fig. 2, a plurality of first insulation insertion pieces 5-3 are provided at intervals between the base plate and the cover plate 5-2. Referring to fig. 5, fig. 5 shows a top view of the first insulating insert 5-3 of the present embodiment. The first heat-preservation inserting pieces 5-3 are in a circular sheet shape and are provided with through holes with the number equal to that of the supporting rods, the through holes are used for fixing the first heat-preservation inserting pieces 5-3, and the positions of the through holes correspond to the positions of the supporting rods. In the embodiment, the number of the through holes is 4, and the first heat-preservation inserting piece 5-3 is arranged on the supporting rod through the through holes. In other embodiments, the number of the through holes corresponds to the number of the support rods. The first heat preservation inserting piece 5-3 is used for controlling the temperature of the first heat preservation barrel. The larger the number of the first heat-preservation inserting pieces 5-3 is, the better the heat-preservation effect is, the larger the size of the first heat-preservation inserting pieces 5-3 and the gap between the first heat-preservation inserting pieces and the process pipe influence the heat-preservation effect and the uniformity of the airflow field of the bottom temperature zone, the larger the first heat-preservation inserting pieces 5-3 are, the smaller the gap between the first heat-preservation inserting pieces and the process pipe is, the better the heat-preservation effect is, but the too small gap can cause turbulence or turbulent flow in the bottom temperature zone and influence the uniformity, so the size of the heat-preservation barrel inserting pieces and the gap between the heat-preservation barrel. In addition, the diameters of the first heat-preservation insertion pieces 5-3 can be the same or different, and the distances between two adjacent first heat-preservation insertion pieces 5-3 can be the same or different. In this embodiment, the first heat-insulating insert 5-3 is made of quartz.

Referring to fig. 2 and 6, fig. 6 shows a top view of an annular shroud according to an embodiment of the invention. A second heat preservation area 11 is arranged above the cover plate 5-2, the second heat preservation area 11 comprises a plurality of second heat preservation inserting pieces 5-4 arranged at intervals, and the second heat preservation inserting pieces 5-4 are arranged at intervals along the axial direction of the process pipe. An annular cover 5-1 is further arranged above the cover plate 5-2, and the annular cover 5-1 surrounds the periphery of the second heat-preservation inserting piece 5-4. The upper end of the second hold-warm zone 11 is located in the process zone and its surrounding temperature is approximately the same as the temperature of the process zone. The process temperature of the prior high-temperature vertical furnace can reach 1200 ℃. Therefore, the material of the annular cover 5-1 is required to have good heat resistance and thermal stability. In this embodiment, the annular cover 5-1 is made of silicon carbide. The top surface of the annular shield 5-1 is used to support the wafer boat. In this embodiment, the top surface of the annular cover 5-1 is an annular plane, and is not deformed at high temperature, so as to provide a stable support surface for the wafer boat. In this embodiment, the boat 3 and the annular cover 5-1 are connected by silicon carbide screws 7.

The cover plate 5-2 is provided with a first locking structure, the annular cover 5-1 is provided with a second locking structure, and the first locking structure and the second locking structure are matched with each other to realize the connection of the cover plate 5-2 and the annular cover 5-2. In this embodiment, the first locking structure is at least two positioning protrusions or positioning grooves distributed along the circumferential direction of the cover plate 5-2, the second locking structure is a matching groove or matching protrusion matched with the positioning protrusions or positioning grooves, and the annular cover 5-1 is locked and unlocked with the cover plate 5-2 in a rotating manner.

Specifically, referring to fig. 2, 7 and 8, the annular cover 5-1 and the quartz cover plate 5-2 are circumferentially positioned by a first L-shaped positioning projection 8-1 and a second L-shaped positioning projection 8-2. The first L-shaped positioning bump 8-1 and the second L-shaped positioning bump 8-2 have the same structure. The first L-shaped positioning lug 8-1 and the second L-shaped positioning lug 8-2 are uniformly distributed in the circumferential direction, when the annular cover 5-1 is installed, the annular cover is placed at the position shown in figure 6, namely the first matching groove 9-1 and the second matching groove 9-2, and then the annular cover is rotated clockwise to be in contact with the first L-shaped positioning lug 8-1 and the second L-shaped positioning lug 8-2 on the surfaces a and b, as shown in figure 8, and the circumferential positioning is completed. When the device is disassembled, the first L-shaped positioning lug 8-1 and the second L-shaped positioning lug 8-2 are positioned in the first matching groove 9-1 and the second matching groove 9-2 by rotating anticlockwise. Meanwhile, after the annular cover 5-1 rotates to be in contact with the first L-shaped positioning lug 8-1 and the second L-shaped positioning lug 8-2, the annular cover 5-1 limits the first L-shaped positioning lug 8-1 and the second L-shaped positioning lug 8-2 in the vertical direction, and at the moment, the annular cover 5-1 cannot move longitudinally due to the fact that the first L-shaped positioning lug 8-1 and the second L-shaped positioning lug 8-2 block the annular cover 5-1 in the vertical direction, and therefore the annular cover 5-1 is prevented from falling. The annular cover 5-1 and the cover plate 5-2 are rotatably mounted and dismounted, the operation is simple, and the stability between the annular cover 5-1 and the cover plate 5-2 can be ensured.

In other embodiments, the first locking structure and the second locking structure may also take other forms, such as a screw connection, a snap connection, or a threaded connection.

The second heat-preservation inserting piece 5-4 is in a circular sheet shape, the function of the second heat-preservation inserting piece is the same as that of the first heat-preservation inserting piece 5-3, and the difference is that the temperature of the area where the second heat-preservation inserting piece 5-4 is located is higher, so that the second heat-preservation inserting piece 5-4 is required to be made of high-temperature-resistant materials. In this embodiment, the plurality of second heat-preserving insertion pieces 5-4 are made of silicon carbide, in another embodiment, a part of the second heat-preserving insertion pieces 5-4 are made of silicon carbide, and another part of the second heat-preserving insertion pieces 5-4 are made of quartz. If the material of the second heat-preservation inserting piece 5-4 in the upper part of the area with higher temperature is silicon carbide, and the material of the second heat-preservation inserting piece 5-4 in the lower part of the area with lower temperature is quartz. The diameter and the number of the second heat-preservation inserting pieces 5-4 and the distance between two adjacent second heat-preservation inserting pieces 5-4 can be adjusted according to a specific process, the invention is not particularly limited, the fixing mode of the second heat-preservation inserting pieces 5-4 can refer to the fixing mode of the first heat-preservation inserting pieces 5-3, and the cover plate 5-2 is provided with the upright posts. In this embodiment, the diameter of the first heat-preserving insert 5-3 is larger than that of the second heat-preserving insert 5-4.

In this embodiment, the annular cover 5-1 covers the bottom of the furnace body temperature zone to ensure that the high temperature part of the chamber is within the range of the annular cover 5-1, the temperature of the upper half part of the second heat preservation area 11 is almost the same as the process temperature to ensure the uniformity of the process area temperature, the second heat preservation area 11 realizes the transition from the process area temperature to the temperature that the first heat preservation area 10 can bear, and reduces the heat transfer from the chamber to the bottom, thereby reducing the temperature of the chamber bottom, avoiding the sealing element from losing efficacy at high temperature, and ensuring that the sealing element realizes reliable sealing. Furthermore, the second heat-insulating insert 5-4 is made of a high-temperature-resistant material, and the second heat-insulating insert 5-4, which is at least positioned in a high-temperature area close to the process temperature at the upper part of the second heat-insulating barrel, is made of a high-temperature-resistant material, so that a better heat-insulating effect is realized.

Having described embodiments of the present invention, the foregoing description is intended to be exemplary, not exhaustive, and not limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A vertical furnace apparatus comprising: the furnace body, be located the technology pipe in the furnace body, be located the boat in the technology pipe and set up in the technology door of the bottom of technology pipe, its characterized in that still includes to be located the intraductal heat preservation device of technology, heat preservation device includes:

2. The vertical furnace apparatus according to claim 1, wherein the cover plate is provided with a first locking structure, the annular cover is provided with a second locking structure, and the first locking structure and the second locking structure are matched with each other to realize the connection between the cover plate and the annular cover.

3. The vertical furnace equipment according to claim 2, wherein the first locking structure is at least two positioning protrusions or at least two positioning grooves distributed along the circumferential direction of the cover plate, the second locking structure is a matching groove or a matching protrusion corresponding to and matching with the positioning protrusions or the positioning grooves, and the annular cover is locked and unlocked with the cover plate in a rotating manner.

4. The vertical furnace apparatus according to claim 1, wherein the top surface of the annular shroud is an annular flat surface.

5. The vertical furnace apparatus according to claim 1, wherein the annular shroud is made of silicon carbide; and/or

6. The vertical furnace apparatus according to claim 1, wherein the heat-retaining base assembly comprises a bottom plate and a support rod disposed above the bottom plate, the support rod penetrates through the first heat-retaining insert to fix the first heat-retaining insert, and a top end of the support rod is fixedly connected to the cover plate.

7. The vertical furnace apparatus according to claim 6, wherein the cover plate and the insulating base assembly are both made of quartz material.

8. The vertical furnace apparatus according to claim 1, wherein the first heat-preserving insert and the second heat-preserving insert are both in the shape of a circular sheet, and the diameter of the first heat-preserving insert is larger than that of the second heat-preserving insert.

9. The vertical furnace installation according to claim 6, wherein the number of the support rods is four, and the four support rods are evenly distributed on the bottom plate.

10. The vertical furnace apparatus according to claim 1, wherein the boat and the annular shield are connected by silicon carbide screws.