JP4435322B2 - Heating device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a heating apparatus that heats a substrate to be processed one by one in a container through a substrate insertion opening.
[0002]
[Prior art]
As one of the semiconductor device manufacturing processes, there is an annealing process for performing uniform processing after performing various processes on a semiconductor wafer (hereinafter referred to as a wafer). A conventional single-wafer heating apparatus for performing this processing includes a chamber 11 that is a container for storing a wafer W, and a wafer insertion port, as schematically shown in a side section and a plane section in FIGS. 5 and 6, respectively. 12 and a gate valve 13, and wafers W are inserted into the chamber 11 one by one from a load lock chamber (not shown) through the gate valve 13 and the wafer insertion port 12, and are placed on the mounting table 14. And heated by heating means such as a lamp (not shown) disposed on the lower side of the chamber 11.
[0003]
At that time, the inside of the chamber 11 is maintained in a predetermined atmosphere, for example, an inert gas atmosphere, and an inert gas is introduced into the chamber 11 by the gas supply means 15 provided on the ceiling portion of the chamber 11, and an exhaust means (not shown) is used. Exhaust.
[0004]
[Problems to be solved by the invention]
In the conventional heating apparatus described above, for example, a plurality of lamps serving as heat sources are arranged concentrically around the center point of the wafer W, and the amount of heating can be adjusted in the diameter direction of the wafer W. As a result, the temperature distribution in the wafer surface can be made uniform. However, while heat rays are reflected on the inner peripheral surface other than the wafer insertion port 12 of the chamber 11, heat rays are absorbed at the wafer insertion port 12, so that the chamber 11 is close to the wafer insertion port 12. The temperature of a part will become lower than another part. Therefore, there is a problem that the heating temperature differs in the circumferential direction of the wafer W, and the processing in the wafer surface becomes non-uniform.
[0005]
The present invention has been made under such circumstances, and an object of the present invention is to absorb heat between a substrate insertion port and an inner peripheral surface of the container in which a substrate to be processed is stored in a single wafer heating apparatus. By providing the same degree of heating, it is possible to increase the uniformity of the heating temperature in the circumferential direction of the substrate to be processed, and to provide a heating apparatus that can perform uniform processing on the substrate to be processed. is there.
[0006]
[Means for Solving the Problems]
A heating apparatus according to the present invention includes a container for storing a substrate to be processed,
Heating means for heating the substrate to be processed;
A substrate insertion opening provided in a part of the side wall portion of the container for taking in and out the substrate to be processed;
In order to make the heat absorption rate of the inner peripheral surface excluding the substrate insertion port of the side wall portion of the container the same as the heat absorption rate of the substrate insertion port , along the circumferential direction along the inner peripheral surface excluding the substrate insertion port. And a groove provided .
[0007]
In the present invention, the heating means can be configured such that the heating amount per unit area can be adjusted for each of a plurality of concentric regions centered on the center of the substrate to be processed.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
1 and 2 are a side sectional view and a plan sectional view, respectively, showing an example of a heating device according to the present invention. In this heating apparatus, the inner peripheral surface 22 of the side wall portion of the chamber 21 for storing wafers W to be processed one by one is removed along the circumferential direction except for the portion of the wafer insertion port 23 that is a substrate insertion port. For example, a groove 24 forming a heat absorbing means is provided. The heat absorption in the groove 24 is almost the same as the heat absorption in the wafer insertion opening 23, and therefore, from the heating means 3 such as the lamp 31 disposed below the opening 20 at the center of the floor of the chamber 21. The heat rays supplied into the chamber 21 through the transmission window 41 that closes the opening 20 from the lower side are uniformly absorbed by all the inner peripheral surfaces 22 of the side wall of the chamber 21 including the wafer insertion port 23. The
[0009]
The groove 24 is preferably an optically black body so that light entering the groove 24 does not exit the groove 24. For example, the ratio of the height and depth of the groove 24 is 1: 3, that is, for example, high The thickness and depth are preferably about 5 mm and 15 mm, respectively. The shape of the groove 24 is not particularly limited as long as the heat absorption in the groove 24 is approximately the same as the heat absorption in the wafer insertion port 23. Note that the inside of the groove 24 may be black to reduce the amount of light that goes out of the groove 24, or the surface inside the groove 24 may be a rough surface with fine irregularities, for example.
[0010]
A gas supply unit 51 called a shower head or the like is provided as a gas supply unit on the ceiling of the chamber 21. The gas supply unit 51 supplies, for example, gas supplied from the gas supply pipes 54 and 55 into the chamber 21 from a large number of gas injection ports 53 of the gas diffusion unit 52. The gas supply means supplies, for example, an inert gas when annealing is performed in an inert gas atmosphere using the heating apparatus, and the film forming apparatus forms a film by a CVD (chemical vapor deposition) method. When used for processing, it is used to supply a film forming gas or the like. The gas supplied by the gas supply means is exhausted through an exhaust means (not shown) provided in the chamber 21. The side wall part of the gas supply part 51 and the gas diffusion part 52 have a fluid passage 56 for allowing a temperature adjusting fluid to flow therethrough.
[0011]
The wafer insertion port 23 is closed by a gate valve 61. When the gate valve 61 is opened, the wafer insertion port 23 is connected to the interior of a load lock chamber (not shown). A holding arm 62 for holding the wafer W and a lifter 63 for raising and lowering the wafer W are provided in the chamber 21. On the other hand, a transfer arm (not shown) for transferring the wafer W is provided in the load lock chamber. When the wafer is opened, the wafer W is transferred between the transfer arm and the holding arm 62.
[0012]
In the chamber 21, a mounting table 25 for mounting the wafer W is provided so as to close the opening 20. In the opening 20, an inert gas such as nitrogen gas can be supplied to a space surrounded by the mounting table 25 and the transmission window 41 by an inert gas supply means (not shown) via an inert gas supply port 42. For example, when this heating apparatus is used as a CVD apparatus, nitrogen gas is uniformly supplied to the vicinity of the lower surface of the wafer W through the gas holes of the buffer plate 43, thereby forming the inside of the chamber 21. A film gas or the like is prevented from flowing into the transmission window 41, and film formation does not occur on the surface of the transmission window 41.
[0013]
The lamps 31 are arranged on a turntable 33 that is driven to rotate by a motor 32, for example. FIG. 3 is a plan view showing an example of the arrangement of the lamps 31. In the example shown in FIG. 3, the lamp 31 is disposed along the circumferences 34, 35, and 36 of, for example, three concentric circles having different radii from the center corresponding to the center point of the wafer. For example, two lamps 31 are provided along the innermost circumference 34, and for example, six lamps 31 are provided along the middle circumference 35, and the outermost circumference is provided. For example, fifteen lamps 31 are provided along the line 36. The number of concentric circles and the number of lamps 31 on each circumference are not limited to the number described above.
[0014]
The lamp 31 can control the heating amount per unit area independently for each of the circumferences 34, 35, 36 or one by one, and the three circumferences 34, 35 can be controlled. , 36, for example, three annular heating regions 37, 38, 39 are formed as schematically shown in FIG. Then, a control device (not shown) controls the heating amount per unit area to be larger in the annular heating region 38 immediately outside the innermost annular heating region 37, and further controls the outer annular heating region 39. In this case, the heating amount per unit area is controlled to be large. Thereby, the heating amount per unit area gradually increases from the center of the wafer W toward the outer periphery, and the in-plane temperature distribution of the wafer W becomes uniform.
[0015]
Next, the operation of the above embodiment will be described. First, the wafer W is loaded into the chamber 21 by a transfer arm (not shown) and transferred onto the holding arm 62 of the lifter 63. Then, while exhausting the chamber 21 by an exhaust means (not shown), a predetermined flow rate of N2 gas is introduced into the chamber 21 through the gas supply section 51 from the gas supply pipes 54 and 55, and the wafer is discharged by the lamp 31 under normal pressure. W is heated to about 500 ° C., for example, and annealing is performed.
[0016]
According to the above-described embodiment, the groove 24 is provided along the circumferential direction on the inner peripheral surface 22 of the side wall portion of the chamber 21 excluding the portion of the wafer insertion port 23, and the portion of the wafer insertion port 23 is removed. Since the heat absorption rate of the inner peripheral surface 22 is approximately the same as the heat absorption rate of the wafer insertion port 23, all the inner peripheral surfaces including the wafer insertion port 23 on the side wall of the chamber 21 are heated by the heat rays in the chamber 21. 22 is uniformly absorbed, the uniformity of the heating temperature in the circumferential direction of the wafer W is increased, and the wafer W can be uniformly processed.
[0017]
In the above, the present invention may provide a black belt-like colored portion without providing the groove 24 along the inner peripheral surface of the side wall portion of the chamber 21. Further, as the heating means, a concentric heater capable of adjusting the temperature in the diameter direction of the wafer W may be used, and the heater may be embedded in a wafer mounting portion in the chamber. Further, the present invention can be applied not only to the annealing process but also to a film forming process by CVD. In this case, for example, the wall surface in the chamber 21 needs to be frequently cleaned with a cleaning gas.
[0018]
【The invention's effect】
As described above, according to the present invention, the heat absorption becomes uniform on all the inner peripheral surfaces including the substrate insertion port of the side wall portion of the container for storing the substrate to be processed. The heating temperature becomes equal, and uniform processing can be performed on the substrate to be processed.
[Brief description of the drawings]
FIG. 1 is a side sectional view showing an example of a heating device according to the present invention.
FIG. 2 is a plan sectional view of the heating device.
FIG. 3 is a plan view showing an arrangement example of lamps of the heating device.
FIG. 4 is a schematic diagram showing a heating region formed by the lamp arrangement.
FIG. 5 is a schematic view showing a side cross section of a conventional single wafer heating device.
FIG. 6 is a schematic view showing a plane cross section of a conventional single wafer heating device.
[Explanation of symbols]
W wafer (substrate to be processed)
3 Heating means 21 Chamber (container)
23 Wafer insertion slot (substrate insertion slot)
24 groove (heat absorption means)

Claims (2)

A container for storing the substrate to be processed;
Heating means for heating the substrate to be processed;
A substrate insertion opening provided in a part of the side wall portion of the container for taking in and out the substrate to be processed;
In order to make the heat absorption rate of the inner peripheral surface excluding the substrate insertion port of the side wall portion of the container the same as the heat absorption rate of the substrate insertion port , along the circumferential direction along the inner peripheral surface excluding the substrate insertion port. And a groove provided . The heating apparatus according to claim 1 , wherein the heating unit is capable of adjusting a heating amount per unit area for each of a plurality of concentric regions centering on the center of the substrate to be processed.

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