TWM516811U - A device for electrical and mechanical connection of a heating element of a heating device and a heating device for heating a susceptor of a CVD reactor - Google Patents

Abstract

The utility model concerns a device for purposes of electrical and mechanical connection of a heating element (10) of a heating device for purposes of heating a susceptor of a CVD reactor with a power supply element (36), having a head (12) for purposes of connecting with the heating element (10), a foot (24) for purposes of connecting with the power supply element (36), and a shaft (21) arranged between the head (12) and the foot (24). For purposes of reducing the temperature gradients it is proposed that the shaft (21) in at least some regions has a smaller cross-sectional area than the head (12), so that the electrical resistance per unit length in the shaft (21) is less than in the head (12). The utility model moreover concerns a heating device for purposes of heating a susceptor of a CVD reactor, the heating element of which is connected with a power supply element (36) using at least one connector.

Description

Heating element for electrically and mechanically connecting a heating device, and heating device for heating the base of the CVD reactor

The present invention relates to a device for electrically and mechanically connecting a heating element and a power supply element of a heating device for heating a base of a CVD reactor, the device having a head for connection to the heating element a leg for connecting to the contact and a stem disposed between the head and the leg.

The invention also relates to a heating device for heating a susceptor of a CVD reactor, the at least one connector being used to connect the heating element of the heating element to a power supply element.

A connector for connecting a heating element of a heating device for heating the base of a CVD reactor is known from US 4,292,504, US 5,759,281 or US 7,645,342.

A hairpin heater is known from US 2,625,635, whereby water is heated. Within the protective tube, a helical heating wire extends in the body of the separator, the heating wire being connected to the terminal contact via a threaded contact pin. The terminal contact has a thread on which the nut is screwed to lock the annular terminal contact. The section of the terminal contact adjoining the threaded section has an embossed section and a flattened section to prevent rotational locking in the casting body.

The CVD reactor has a reactor housing, an air intake device disposed within the reactor housing, and the process gas is introduced into the processing chamber using the air intake device. The processing chamber has a pedestal on which the substrate to be coated is located. In order to bring the substrate to the coating temperature, the susceptor is heated from below by means of thermal radiation. A heating device according to the present invention is used in order to generate heat radiation. According to this The novel heating device has a power supply element, for example a power supply element in the form of a contact plate, which protrudes from the contact plate. Each connector is coupled to at least one heating element. Both ends of each heating element are connected to two different power supply elements using a connector such that current can be conducted through the heating element via the power supply element. Here, the heating element heats up and transfers its heat to the susceptor in the form of heat radiation. Here, the heating element is heated until it is incandescent. The extremely high temperature resistant heating element consists of tungsten wire. The connector can also be made of tungsten, but it can also be made of stainless steel or molybdenum. Since the connector has a significantly larger diameter than the heating element, the connector has a significantly lower ohmic resistance per unit length than the heating element. This situation results in a very high temperature difference (temperature gradient) at the point of connection of the heating element to the head of the connector.

It is an object of the invention to provide a measure for reducing this temperature difference.

This object is achieved by the present invention as specified in the scope of the patent application, which relates to a specially developed connector and also to a heating device having the connector developed thereby.

First and foremost, the stem of the connector has at least a partial cross-sectional area that is smaller than the head. Thereby, the resistance per unit length in the direction in which the contact extends in the stem portion is larger than that in the head portion, so that a heat output per unit length larger than that in the head portion is generated in the stem portion. Preferably, the head of the connector has a larger cross-sectional area than a threaded cross-sectional area of a wound wire forming the heating element. The wire forming the heating element is preferably a tungsten wire. The two heating wires can extend side by side and form a double helix. The cross-sectional area of the head is preferably more than twice the cross-sectional area of the stem. The connector preferably has a linear extension. One end of the connector forms the head. The other end of the connector forms a leg. The stem extends between the head and the leg. The length of the stem is preferably greater than the diameter of the stem. The stem portion, the head portion and the leg portion each have a circular cross-sectional area, wherein the cross-sectional area of the leg is greater than the cross-sectional area of the stem portion. The cross-sectional area of the leg may correspond to the head The cross-sectional area. In the case of forming a tapered section, the generally cylindrical head can transition to the reduced diameter portion of the stem. In the case of forming a tapered section, the shank can in turn transition to the leg. The head and the leg may be integrally formed with the stem. The connector can thus be formed as a milled part. In a variant of the invention, it is provided that the head has a passage with a substantially circular cross section. The opening can be open toward the end face of the head. The axis of the opening preferably extends transversely to the direction of extension of the stem. A heating element, in particular a wound heating wire, can be inserted into this channel. A fastener is provided by which the heating element can be secured in the channel. The fastener can be in the form of a countersunk bolt that is threaded through a threaded hole in the wall of the passage opening. In another variation, the head can form a contact arm. The contact arm can extend from the head in a direction transverse to the axis of the stem. The contact arm can be formed as an insert and inserted into one of the sockets of the head using an insertion section. The contact arm is coupled to the heating element. If the heating element is a wound heating wire, the heating wire can be screwed to the contact arm to some extent. Here, each turn of the heating wire is located in the groove of the thread of the contact arm. A sleeve can be placed over the heating wire. The contact arm is then preferably inserted into the sleeve. The inner wall of the sleeve abuts against the coil of the heating element. In a further configuration variant of the foot of the connector, it is provided that the leg has a conical section. In this case, the conical section is in the form of a truncated cone section which preferably adjoins a cylindrical section. The leg of the connector is inserted into a tapered bore of a contact plate by means of the truncated cone section. Thereby a desired contact surface is provided between the connector and the contact plate. An externally threaded portion is attached to the end of the tapered section where the diameter is reduced, and a fixing nut can be screwed onto the externally threaded portion. The nut is supported on the bottom side of the contact plate by inserting a spacer. A stop is provided to prevent the nut from being released from the external thread during heating or cooling of the heating device. The stopper may be a shape engaging member that is inserted through an opening of the externally threaded portion. The stopper may have a tongue that is bendable so as to abut against a polygonal surface of the nut or inserted into an axial groove of the outer wall of the nut, thereby avoiding the snail The mother rotates.

The particular configuration of the head (ie, the channel and/or the contact arm) and the particular configuration of the leg (ie, a tapered contact surface that abuts against a tapered wall of one of the holes) is relative An innovative and innovative design of the prior art.

The examples of the embodiments of the present invention are explained below in conjunction with the accompanying drawings.

Figure 1 shows the basic construction of a CVD reactor in which, for the sake of brevity, a large number of components required to operate a CVD reactor are not shown. In the airtight housing 1, there is an intake device 2 which inputs a process gas, a carrier gas and a flushing gas using an air supply line not shown. These gases enter the processing chamber 3 through the gas outlet, the bottom of the processing chamber being formed by the susceptor 5, and the coated substrate 4 being located on the susceptor. Here, the substrate may be a germanium substrate or a III-V main group element substrate, and a semiconductor layer, an insulating layer or a conductor layer may be deposited on the substrate. The susceptor 5 made of graphite is heated by the heating device 6 from below.

The intake device 2 disposed above the processing chamber 3 is actively cooled. This results in a steeper temperature gradient between the heating device 6 and the intake device 2. The heating device 6 must deliver a sufficient amount of heat so that the surface of the susceptor 5 facing the processing chamber 3 is heated to above 1000 °C.

At this temperature, the gaseous process gas entering the process chamber reacts with the organometallic compound of the III or II main group element and the hydride of the IV, V or VI main group element.

Figures 2 through 4 show a general heating device, as shown schematically in Figure 1. The heating device 6 is composed of three heaters 7, 8, 9. The middle heater is formed by a disc-shaped heater 7, which is surrounded by two annular heaters 8, 9. Each of the three coaxially nested heaters 7, 8, 9 can be individually powered independently of the other heaters.

Each of the heaters 7, 8, 9 has one or more heating elements 10 that are wound into a helix around a common center of the heating device. A plurality of heating elements 10 are successively provided on the spiral, each of which is connected to the contact plate via a connector 11. The contact plate acts as a power supply element 36 to provide a power supply such that current can flow through the heating element 10. The heating element 10 is not shown in detail for the sake of brevity.

Figures 5 to 7 show a first embodiment of the invention for connecting the heating element 10 to the power supply element 36.

The heating element 10 is a double-strand heating wire composed of two spirally wound tungsten wires. The heating element 10 extends on a plane parallel to the plane of the power supply element 36. The end of the heating element 10 (i.e., the last few turns of the heating wire) is connected to the power supply element 36 by a connector 11.

The connector 11 has a head 12 having a channel 14 having a circular cross section. The channel axis extends transverse to the longitudinal axis of the connector 11. The spiral coil of the heating element 10 is located in the channel. The passage 14 is open toward the end face of the head 12. The heating element 10 can be secured in the passage 14 by means of a countersunk bolt 15 which is screwed into the threaded bore of the wall of the passage 14.

The head 12 has a generally circular cross section. The channel 14 is located in a cylindrical section belonging to the end of the connector 11. In the case of forming the tapered section 22, the cylindrical section forming the head transitions to the cylindrical stem 21. The axis of the stem 21 defines the longitudinal axis of the connector 11. The diameter of the stem portion 21 is smaller than the diameter of the head portion 12. The cross-sectional area of the stem portion 21 is 50% smaller than the cross-sectional area of the head portion 12.

A further conical section 23 is adjoined on the stem 21, this section transitioning to a section 25 of increased diameter. Here, the increased diameter section is in the form of a cylindrical section 25 having a diameter equal to the diameter of the head 12. The cylindrical section 25 also has a circular horizontal section.

The cylindrical section 25 belongs to the foot 24 of the connector 11 with which the connector 11 is connected to the power supply element 36. To ensure as large a contact as possible between the connector 11 and the power supply element 36, the leg 24 has a tapered truncated section 26 that is inserted into the tapered bore 37 of the power supply element 36.

The positioned end of the connector 11 opposite the head 12 is formed by an externally threaded section 27 on which the nut 35 is screwed. The nut 35 is supported on the underside of the power supply element 36 by placing a spacer 34 (the frusto-conical section 26 can extend through the spacer) in the middle to apply a tensile stress on the frustoconical section 26.

The connector 11 is substantially rotationally symmetric with its head 12, stem 21 and legs 24 having a common axis of extension. The connector 11 can be formed as a milled piece. A cylindrical blank can be used, wherein the stem portion 11 and the tapered sections 22, 23, 26 and the externally threaded section 27 can be formed by cutting.

Thermodynamic motion occurs during heating and cooling. Here, a stop 31 is provided in order to prevent the nut 35 from coming loose from the externally threaded section 27. The stopper 31 is a small plate with a tongue 32. The tongue forms the T-shaped long side of the T-shaped body. The two T-shaped sides 33 form a fixed tab. The tongue 32 is inserted through the externally threaded section 27 in the narrower transverse opening 29. The end of the tongue 32 is then bent upwardly towards the nut so as to abut against one of the polygonal faces of the nut 35.

The slit 29 is open to the end face 28 of the externally threaded section 27 by means of the slit section 30. Thereby, the slit for inserting the tongue 32 of the stopper 31 has a T-shaped cross section.

The embodiment illustrated in Figures 8 to 13 differs from the first embodiment primarily in terms of the shape of the nut 35 and the electrical contact formation between the heating element 10 and the head 12. Here, the nut 35 is designed as a knurled nut. The knurled nut has an axially extending groove that alternates with the axially extending tabs. An upwardly curved tongue 32 of the stop 31 can be inserted into the slot. The head 12 of the connector 11 has an opening 17 into which the insertion end of the contact arm 16 is inserted. The contact arm 16 thus extends transversely to the direction in which the connector 11 (i.e., the stem 21 of the connector 11) extends. An internal thread 18 is positioned on the free end of the contact arm 16 that extends transversely to the head 12. The section of the contact arm 16 carrying the internal thread 18 is designed to be slightly conical. The head 12 defines a recess 19 having a concave configuration. The wall extending transversely to the recess 19 has an opening of the opening 17 from which the section of the thread 18 of the contact arm 16 projects.

The contact arm 16 is screwed into the spiral heating element 10 by its thread 18 so that the heating wire fits into the groove of the pitch.

These two embodiments serve not only to fix the heating element in a mechanical form, but also to supply power to the heating element 10.

Since the diameter of the heating element 10 is significantly smaller than the diameter of the connector 11, the heating element 10 has a significantly greater resistance per unit length than the connector 11, which results in a voltage drop across the length of the connector 11 that is significantly less than the voltage drop across the same length of the heating element 10. Therefore, the heating element 10 is also heated significantly more intensely than the connector 11. The heating element is heated to a temperature above 1000 °C. In view of the reduced diameter section formed by the stem portion 21, the resistance per unit length in the region of the connector 11 is reduced. This situation results in the connector 11 being also significantly heated in the region of the stem. This situation results in a temperature gradient of the head 12 that is less than a temperature gradient of the larger diameter stem 21.

In the embodiment illustrated in Figures 14 and 15, the sleeve 20 is inserted over the contact arm 16. The sleeve extends over the entire contact arm 16 and abuts against the side of the recess 19 in which the opening 17 is formed. The sleeve 20 extends in the lateral direction of the extending direction of the connector 11. The heating element 10 bears against the inner wall of the sleeve 20 and is thus mechanically fixed in the swirl of the thread 18.

The contact arm 16 is preferably also made of tungsten. The insertion end of the contact arm 16 can be secured in the opening 17 using an unillustrated bolt or cotter pin. The insertion end can also be designed to be slightly conical so that the conical surface on the inner wall abuts the opening 17 which is likewise conical.

The above embodiments are intended to illustrate the novels that are integrally included in the present application, and the present invention provides an inventive improvement to the prior art at least by the combination of the following technical features, namely: a device in which the stem portion 21 has at least a portion than the head portion 12 smaller cross-sectional area; a device in which the cross-sectional area of the stem 21 is 50% smaller than the cross-sectional area of the head 12; a device in which, in particular in the case of the formation of the tapered section 22, a prototype cross-section The head 12 of the section transitions to a stem 21 having in particular a circular cross section, wherein the length of the stem 21 is greater than its diameter; a device in which the cross-sectional area of the leg 24 is larger than the cross-sectional area of the stem, and in particular Approximately equal to the cross-sectional area of the head 12; A device wherein the axial length of the head 12 is approximately equal to the diameter of the head 12; a device wherein the heating element 10 is formed from at least one wound wire; a device wherein the head 12 has a transverse direction 21 Extending the direction of the passage 14 for accommodating the heating element 10, the heating element being fixed in the channel 14 in particular by means of a bolt 15; a device in which the head 12 has a contact arm 16 carrying a heating element 10, wherein the heating element 10 in particular formed by two wires which are wound side by side and which are situated in the groove of the thread 18 of the contact arm 16 and in particular define that a helical coil section located in the groove of the thread 18 is inserted into the sleeve 20; Where the leg 24 has a truncated cone section 26 which is inserted into a conical bore 37 forming a contact plate of the feed element 36, wherein in particular a reduced diameter end portion of the truncated cone section 26 is provided Adjacent to the segment is an externally threaded section 27 , the nut 35 being screwed onto the externally threaded section 27 , wherein in particular the nut 35 is rotationally locked by means of the stop 31 .

A device in which the head 12 forms a contact member (e.g., channel 14, contact arm 16) by which the heating element 10 formed by the helical coil can be mechanically and electrically coupled to the head 12; a device in which the leg 24 There is a truncated cone section 26 which transitions through its base end to the externally threaded section 27.

All published features (both themselves and their mutual combinations) have new meaning or value. In the disclosure of the present application, the disclosure of the affiliated/affiliated priority text (prior application document) is also fully included, and the feature in the priority text is also included in the patent application of the present application. In the scope. The alternative side-by-side design schemes in the dependent claims are all improved designs with independent new meanings or values for the prior art, and in particular, the divisional claims can be filed based on these dependent claims.

1‧‧‧ CVD reactor

2‧‧‧air inlet

3‧‧‧Processing room

4‧‧‧Substrate

5‧‧‧Base

6‧‧‧ heating device

7‧‧‧heater

8‧‧‧heater

9‧‧‧heater

10‧‧‧ heating elements

11‧‧‧Connector

12‧‧‧ head

13‧‧‧ end face

14‧‧‧ passage

15‧‧‧ bolt

16‧‧‧Contact arm

17‧‧‧ openings

18‧‧‧ thread

19‧‧‧ recess

20‧‧‧ casing

21‧‧‧ pole

22‧‧‧Conical section

23‧‧‧Conical section

24‧‧‧ feet

25‧‧‧Cylindrical section

26‧‧‧Cut cone section

27‧‧‧External thread section

28‧‧‧ end face

29‧‧‧ gap

30‧‧‧Slit section

31‧‧‧stops

32‧‧‧ tongue

33‧‧‧Retaining tabs

34‧‧‧shims

35‧‧‧ nuts

36‧‧‧Power supply components

37‧‧‧Conical hole

Figure 1 shows only a cross-sectional view of the main components of the CVD reactor; Figure 2 shows a side view of a heating device having a total of three heating zones; Figure 3 shows a top view of the heating device; Figure 4 shows a cross-sectional view taken along line IV-IV of Figure 3; Figure 5 shows the first of the connectors Figure 6 shows a perspective view of the connector of Figure 5; Figure 7 shows a second side view of the connector of Figure 5; Figure 8 shows a perspective view of a second embodiment of the connector; A cross-sectional view taken along line IX-IX of Fig. 8; Fig. 10 shows a cross-sectional view taken along line XX of Fig. 8; Fig. 11 shows a partial enlarged view of Fig. 10; Fig. 12 shows a view along arrow XII of Fig. 10. FIG. 13 shows an exploded view of the embodiment shown in perspective view in FIG. 8; FIG. 14 shows a perspective view of the third embodiment, and FIG. 15 shows a cross-sectional view taken along line XV-XV of FIG.

10‧‧‧ heating elements

11‧‧‧Connector

12‧‧‧ head

13‧‧‧ end face

21‧‧‧ pole

22‧‧‧Conical section

23‧‧‧Conical section

24‧‧‧ feet

25‧‧‧Cylindrical section

26‧‧‧Cut cone section

27‧‧‧External thread section

28‧‧‧ end face

34‧‧‧shims

35‧‧‧ nuts

36‧‧‧Power supply components

37‧‧‧Conical hole

Claims (18)

A device for electrically and mechanically connecting a heating element (10) to a heating element (10) and a power supply element (36) for heating a susceptor (5) of a CVD reactor (1) The device has a head (12) for connection to the heating element (10), a leg (24) for connection to the power supply element (36), and a head (12) disposed thereon a stem portion (21) between the leg portion (24), wherein the stem portion (21) at least partially has a smaller cross-sectional area than the head portion (12), thereby causing the stem portion (21) to be inside The resistance per unit length is greater than the resistance per unit length in the head (12). The device of claim 1, wherein the cross-sectional area of the stem portion (21) is 50% smaller than the cross-sectional area of the head portion (12). The device of claim 1 or 2, wherein in the case of forming a tapered section (22), the head (12) transitions to the stem (21) having a circular cross section, wherein the stem The length of (21) is greater than its diameter. The device of claim 3, wherein the head has a circular cross section. The device of claim 1 or 2, wherein the cross-sectional area of the leg (24) is greater than the cross-sectional area of the stem. The device of claim 5, wherein the cross-sectional area of the leg (24) is approximately equal to the cross-sectional area of the head (12). The device of claim 1 or 2, wherein the axial length of the head (12) is approximately equal to the diameter of the head (12). The device of claim 1 or 2, wherein the heating element (10) is formed from at least one strand of wound wire. A device according to claim 1 or 2, wherein the head (12) has a passage (14) for receiving the heating element (10), the heating element being fixed in the passage (14). The device of claim 9, wherein the channel (14) is transverse to the direction in which the stem portion (21) extends extend. The device of claim 9, wherein the heating element (10) is secured in the channel (14) by a bolt (15). The device of claim 1 or 2, wherein the head (12) has a contact arm (16) carrying the heating element (10), wherein the heating element (10) is formed by wires that are wound side by side, such as The wire is located in a slot of a thread (18) of the bolt (15). The device of claim 12, wherein the helical coil section located within the slot of the thread (18) is inserted into a sleeve (20). The device of claim 1 or 2, wherein the leg (24) has a truncated cone section (26), the truncated cone section (26) being inserted into a cone forming a contact plate of the power supply element (36) Inside the hole (37). The device of claim 14, wherein an outer threaded section (27) is abutted on the reduced diameter end section of the frustoconical section (26), a nut (35) can be screwed onto the external thread, The nut (35) is rotationally locked by means of a stop (31). A device for electrically and mechanically connecting a heating element (10) of a heating device (6) with a power supply element (36) for heating a base of a CVD reactor (1) (5) the device has a head (12) for connection to the heating element (10), a leg (24) for connection to the power supply element (36), and a head (24) disposed thereon (12) a stem portion (21) between the leg (24), wherein the head portion (12) forms a contact member by which a heating element (10) formed by a spiral coil is The head (12) is mechanically and electrically connected. A device for electrically and mechanically connecting a heating element (10) of a heating device (6) with a power supply element (36) for heating a base of a CVD reactor (1) (5) the device has a head (12) for connection to the heating element (10), a leg (24) for connection to the power supply element (36), and a head (24) disposed thereon (12) a stem portion (21) between the leg (24), wherein the leg (24) has a cut A tapered section (26) that transitions through its base end to an externally threaded section (27). a heating device for heating a base (5) of a CVD reactor (1), the heating device having a power supply element (36) and at least one heating element (10), wherein the heating element (10) A device according to any one or more of claims 1 to 17 is connected to the power supply element (36).