JP5468895B2 - Heating apparatus and substrate processing apparatus - Google Patents

Description

  The present invention relates to a heating apparatus and a substrate processing apparatus for heating an object to be heated.

  In a semiconductor manufacturing apparatus and a magnetic head manufacturing apparatus, a heating apparatus is used to heat a substrate such as a wafer as an object to be heated. If the heating of the substrate by this heating device is made non-uniform, the film quality such as crystallinity becomes non-uniform in the surface of the substrate, and the electrical characteristics such as the thickness and resistivity of the thin film formed on the substrate in a later process May become uneven. For this reason, a heating apparatus that uniformly heats an object to be heated such as a substrate is desired.

JP 2007-115751 A JP 2002-217110 A

  As described above, it is desirable that the temperature distribution in the substrate surface to be heated is uniform, but when the wafer is heated in a non-contact manner with respect to the heating device, the temperature of the outer peripheral portion is lower than that near the center of the wafer. Tend to be. In order to increase the temperature on the outer peripheral side of the wafer, a plurality of heating devices (heaters) are used, and the temperature distribution is controlled on the inner peripheral side and the outer peripheral side (Patent Document 1). There is a method (Patent Document 2) in which a reflector that reflects heat and light escaping to the outside is provided around the wafer.

  However, when a plurality of heaters are used, a plurality of power supplies and their control are required, which increases the cost and requires complicated control. In addition, when the reflector is used, the amount of heat transferred to the entire surface of the wafer is increased and the utilization efficiency of the heat and light of the heater can be improved, but the temperature distribution in the substrate surface cannot be made uniform. In addition, when a reflector is installed around the wafer, it is necessary to form an opening for loading and unloading the wafer in the reflector. However, since the temperature near the opening tends to be low, temperature control near the opening is extremely difficult. It becomes important to.

  In order to solve the above problems, a heating apparatus of the present invention includes a chamber having an opening through which a heated body is carried in and out, a heater provided in the chamber for heating the heated body, and the inside of the chamber A holding mechanism for holding the heated body, and a reflector for reflecting heat from the heater toward the heated body, the reflector sandwiching the heater between the heater It was arranged on the opposite side to the object to be heated, and the area of the reflector near the opening was enlarged compared to other positions.

  The substrate processing apparatus of the present invention includes a heating chamber including the heating device, a film forming chamber for performing a film forming process on the substrate as the object to be heated, and the substrate as the heating chamber or the film forming chamber. And a transfer chamber that carries in and out between them.

  According to the present invention, the in-plane temperature of the heated object can be made uniform.

1 is a plan view of a substrate processing apparatus according to an embodiment of the present invention. FIG. 2 is a side view of the substrate heating chamber shown in FIG. 1. It is a top view of the substrate heating chamber shown in FIG. It is a top view of a back reflector. It is a top view of the conventional back reflector. It is a temperature distribution figure at the time of using the reflector of this embodiment. It is a temperature distribution figure at the time of using the conventional reflector. It is a side view of the substrate heating chamber of other embodiments. It is a top view of the substrate processing apparatus of another embodiment. FIG. 10 is a plan view of the substrate heating chamber shown in FIG. 9.

  EMBODIMENT OF THE INVENTION Below, the form for implementing this invention with reference to an accompanying drawing is demonstrated in detail. The embodiment described below is an example for realizing the present invention, and should be appropriately modified or changed according to the configuration and various conditions of the apparatus to which the present invention is applied. It is not limited to the embodiment.

[Embodiment 1]
First, the substrate processing apparatus according to the first embodiment will be described with reference to FIGS. As shown in FIG. 1, a substrate processing apparatus will be described with respect to a substrate substrate heating chamber and a substrate processing apparatus. As shown in FIG. 1, the cluster type substrate processing apparatus includes a substrate heating chamber 1, a film formation processing chamber 2, a substrate transfer chamber 3, and a substrate carry-in / out chamber 4. The substrate heating chamber 1, the film formation processing chamber 2, and the substrate carry-in / out chamber 4 are connected to the substrate transfer chamber 3. Note that one or a plurality of substrate heating chambers 1 and film formation processing chambers 2 can be connected to the transfer chamber 3 in accordance with the substrate processing procedure.

  The substrate heating chamber 1 is partitioned from the substrate transfer chamber 3 by a slit valve 6 as shown in FIGS. When the substrate W is transferred from the substrate transfer chamber 3 to the substrate heating chamber 1, the slit valve 6 is opened, the substrate W is held by the substrate chuck 21 of the pair of transfer robots 20 mounted in the substrate transfer chamber 3, and the substrate It is carried into the heating chamber 1. When the substrate W is unloaded from the substrate heating chamber 1, the transfer robot 20 may perform an operation opposite to the above. The pair of transfer robots 20 have a function of transferring the substrate W between the substrate chucks 21 on the substrate mounting table provided at the center of the substrate transfer chamber 3.

  As shown in FIG. 2, the substrate heating chamber 1 is made of a heater 10 that is a heating device on a substrate stage 15 and a heat-resistant material such as quartz glass, and a material that is highly permeable to heat radiation from the heater 10. The heater cover 9 and the heater mounting base 13 and the support pins 11 for mounting the substrate W are provided. In a state where the substrate W is placed on the support pins 11, the substrate W is heated by the heat of the heater 10 while the back surface of the substrate W and the heater cover 9 are not in contact with each other. The heater cover 9 and the substrate W may be brought into contact with each other. However, non-contact can prevent contamination due to a substance adhering to the side surface of the substrate W, and also prevent occurrence of uneven heating of the substrate W. . The surface temperature of the heater cover 9 is measured by a thermocouple 17 installed between the substrate W and the heater cover 9, and the heat generation state of the heater 10 is controlled by feeding back the measurement result so that the temperature converges to a predetermined value. To do.

  Although not shown, the substrate heating chamber 1 is connected to an exhaust system such as a dry pump. For example, the substrate W is heated in a reduced pressure state of 0.1 Pa or less in the chamber, thereby forming a film forming material such as oxidation. Prevents deterioration. Further, a gas introduction system may be added in addition to the above-described exhaust system, and exhaust may be performed between substrate heatings, and an inert gas such as Ar gas may be introduced during heating.

  The substrate heating chamber 1 also includes an upper reflector 7, a side reflector 8, and a back reflector 14 for reflecting heat radiation from the heater 10 to a substrate (here, a wafer) W as an object to be heated.

  As shown in FIG. 3, the side reflector 8 has a shape surrounding the side of the wafer W. However, since the wafer W needs to be transferred, the side reflector 8 is interposed between the slit valve 6 serving as a transfer path of the wafer W and the wafer W. An opening 8a is formed. The side reflector 8 and the upper reflector 7 are made of a material that can reflect heat and light (infrared rays) radiated from the heater 10, and for example, stainless steel and Mo alloy that are excellent in heat resistance and workability are suitable. .

  The side reflector 8 having the opening 8a is close to the opening 8a because the heat radiated from the heater 10 escapes from the slit valve 6 through the opening 8a and is not efficiently reflected near the slit valve 6 side. The in-plane temperature of the wafer W becomes lower than other surface positions.

  The present invention pays attention to such a technical problem. As shown in FIG. 4, a back reflector 14 is provided at positions corresponding to the back side and the outer peripheral side of the wafer W in the substrate heating chamber 1. The area 14a at a position close to the opening 8a for transporting the wafer W is enlarged as compared with other positions. As a result, a decrease in the in-plane temperature of the wafer W at a position close to the outer peripheral side of the wafer W and the opening 8a can be suppressed. As a result, the temperature distribution of the wafer W can be improved, and the resistivity of the thin film can be improved. Can be improved.

  Specifically, the back reflector 14 is configured by a member that has a higher reflectance than the substrate stage 15 for the heat radiation from the heater 10. Here, the surface of the substrate stage 15 on the wafer W side remains the same as that at the time of molding, but the reflectance can be increased by applying a mirror treatment to the surface of the back reflector 14 on the wafer W side. Further, the back reflector 14 is made of a material that can reflect heat and light from the heater 10, and for example, stainless steel, Mo alloy, etc. that are excellent in heat resistance and workability are used. Note that the back reflector 14 may be made of a material having a higher reflectance than the substrate stage 15 to increase the amount of heat received on the outer peripheral side of the wafer W.

  As described above, by enlarging the area 14a of the back reflector 14 at a position close to the opening 8a of the side reflector 8 as compared with other positions, more heat and light escaping from the vicinity of the opening 8a are reflected than before. The temperature drop of the wafer W at the position corresponding to the opening 8a can be suppressed, and the temperature in the substrate surface can be made uniform.

  As another embodiment, as shown in FIG. 8, the heater 10 may be arranged above the wafer W. In this case, the back reflector 14 is disposed on the heater 10.

  As shown in FIG. 9, when the chamber 30 is also connected to the opposite side of the substrate heating chamber 1 from the substrate transfer chamber 3 via the slit valve 6, the side reflector 8 is as shown in FIG. Since the opening 8a is formed at two opposite positions, the path through which heat and light escape increases, and the temperature distribution in the substrate surface further deteriorates. Therefore, as shown in FIG. 10, the temperature distribution can be improved by enlarging the area of the side reflector 8 at the position 14a adjacent to each opening 8a. That is, the area of the back reflector 14 at one or more locations corresponding to the plurality of openings 8a may be enlarged.

  The shape of the reflective surface of the back reflector 14 is not limited to the arc shape described above. Further, the shape in the thickness direction is not limited to a uniform shape. For example, the reflection amount may be finely adjusted so as to become thinner inward in the radial direction of the wafer W that becomes high temperature. Similarly, it is possible to make a fine adjustment so that the amount of reflection decreases inward in the radial direction, for example, by forming a back reflector using materials having different reflectivities, or by performing a specular treatment partially. Good.

  In applying the present invention, it is not always necessary to provide an upper reflector or a side reflector, but by using these and a rear reflector in common, heat utilization efficiency is improved.

  In the above embodiment, the upper reflector 7 and the side reflector 8 have a large irradiation angle that is not incident on the wafer W or reflect heat or light that has been scattered by the wafer W, and the amount of heat transfer is large. The size and variation of the reflection angle are large, and it is unsuitable for causing reflection on a specific portion of the wafer W, and it is suitable for improving the reflection amount as a whole by providing the entire periphery of the wafer W.

  On the other hand, the back reflector 14 increases the amount of heat and light reflected to the outer peripheral side rather than the inner peripheral side of the wafer W. That is, since the radiated light that hardly receives scattering or the like is incident on the back reflector 14, the reflection angle is small and the reflection position is specified. For this reason, the in-plane distribution of the temperature difference can be improved with high accuracy. Compared with the case where the heat generation of the heater 10 is controlled separately on the inner and outer peripheral sides, partial adjustment is easy, the configuration can be made at low cost, and the power consumption is low.

  Further, by disposing the reflector so as to face the front surface or the back surface side of the wafer W and enlarging the area of the position close to the opening 8a, the position corresponding to the opening 8a for transporting the substrate where heat easily escapes. The wafer surface temperature is increased. Thereby, it is particularly suitable for adjusting a portion where a temperature difference is constantly generated.

[Test results]
A test for confirming the effect of the present invention that the in-plane temperature distribution of the wafer W can be made uniform by the back reflector 14 of the present embodiment was performed.

  FIG. 7 shows the test results when the annular back reflector 16 having a constant peripheral edge width shown in FIG. 5 is used, and the back reflector 14 is used in which the area of the position 14a close to the opening 8a shown in FIG. 4 is enlarged. FIG. 6 shows the test results obtained when the test was performed. When the back reflector 16 shown in FIG. 5 is used, the temperature close to the slit valve 6 is low, whereas when the back reflector 14 shown in FIG. 4 is used, a substantially uniform temperature distribution in the wafer surface. It has become. For example, when heated to 400 ° C., the distribution value defined by distribution = (maximum temperature−minimum temperature) / 2 is 4.5 ° C. in FIG. 7 and 2.8 ° C. in FIG. It can be seen that the distribution has improved.

Claims (8)

A chamber having an opening through which an object to be heated is carried in and out;
A heater provided in the chamber for heating an object to be heated;
A holding mechanism provided in the chamber for holding the object to be heated;
A reflector for reflecting the heat from the heater toward the object to be heated,
The said reflector is arrange | positioned on the opposite side to the said to-be-heated body on both sides of the said heater, The area of the position near the said opening part in the said reflector was expanded compared with the other position.   The heating apparatus according to claim 1, wherein a plurality of the openings are provided.   The heating apparatus according to claim 1, wherein the reflector is made of stainless steel or molybdenum.   The heating device according to any one of claims 1 to 3, wherein the heater is formed of a heating resistor.   The heating device according to any one of claims 1 to 3, wherein the heater is a heating mechanism using a lamp.   The said reflector is provided with the 2nd and 3rd reflector arrange | positioned at the upper part and side part of the said to-be-heated body, The heating apparatus of Claim 1 characterized by the above-mentioned.   7. The heating apparatus according to claim 1, wherein at least a part of the surface of the reflector on the side to be heated is mirror-finished. 7. A heating chamber comprising the heating device according to any one of claims 1 to 7,
A film forming chamber for performing a film forming process on the substrate as the object to be heated;
A substrate processing apparatus comprising: a transfer chamber for transferring the substrate to and from the heating chamber or the film formation chamber.