JP2004103630A - Shower head and semiconductor thermal treatment apparatus using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor thermal treatment apparatus which is capable of restraining a reactive gas from being decomposed as the gas comes into contact with an object other than a semiconductor substrate, and of making the reactive gas reacting on the surface of the semiconductor substrate nearly uniform in concentration throughout the surface of the semiconductor substrate. <P>SOLUTION: A shower head is used for feeding the reactive gas on the surface of the semiconductor substrate as the gas is kept uniform in concentration through the surface of the substrate and for exhausting the reactive gas. Gas feed/exhaust hole units each composed of reactive gas feed holes and reactive gas exhaust holes are provided on the shower head with equal intervals, a cooling means is provided to the shower head, a feed gas storage region and an exhaust gas storage region are provided inside the shower head, the feed gas storage region is connected to the reactive gas feed holes with feed capillaries, and the exhaust gas storage region is connected to the reaction gas exhaust holes with exhaust capillaries. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present technology relates to semiconductor device manufacturing, and relates to an apparatus for heat-treating a semiconductor substrate in a reactive gas atmosphere for forming an oxide film, a nitride film, and the like.
[0002]
[Prior art]
In a manufacturing process of a semiconductor device, heat treatment is an important technique applied along with formation of an oxide film, a nitride film, and the like on a semiconductor substrate. For example, in the case of an oxide film forming step, an oxide film is formed on the surface of a silicon substrate by performing a heat treatment in an oxidizing atmosphere gas represented by oxygen. Hereinafter, for convenience of explanation, the oxide film forming step will be described as an example.
[0003]
As a heating means, a diffusion furnace using heat radiation has conventionally been used, and it is widely and generally used because a plurality of semiconductor substrates can be uniformly heat-treated. FIG. 7 is a configuration diagram of a conventional diffusion furnace using thermal radiation. The diffusion furnace shown in FIG. 7 includes a boat 101 serving as a jig for mounting a plurality of semiconductor substrates 102, a tube 103 serving as a housing serving as a reaction chamber for processing semiconductor substrates, and a uniform temperature of the tubes 103. And a heater 108 for heating the tube 103, an intake pipe 115 for supplying a heat conductive medium, and discharging used heat conductive medium. An exhaust pipe 117, an exhaust device 118, an intake device 116, and a gas inlet 105 are configured.
[0004]
The boat 101 on which the semiconductor substrate 102 is mounted is housed in a tube 103, and the semiconductor substrate 102 is subjected to a reaction process by a reaction gas supplied into the tube 103 from a gas inlet 105.
The heat transfer medium supplied by the suction device 116 uniformly conducts the heat generated by the heater 108 while passing through the heat equalizing tube 104, and is exhausted by the exhaust device 118 after use.
The reaction gas is led from the gas inlet 105 to the inside of the housing 103 and used for various processes of the semiconductor substrate 102.
[0005]
As another heating means in an oxygen atmosphere, an RTP (Rapid Thermal Processing) device is known. FIG. 8 is a diagram showing a conventional RTP device.
In the case of FIG. 8, the semiconductor substrate 102 is placed on the boat 101, inserted into the tube 103, and rapidly heated from the outside by the halogen lamp 107. At this time, the gas can be heated to a high temperature in a short time by introducing a gas according to the application from the gas inlet 105. Since a large amount of power is supplied to the lamp, the lamp temperature rises, and sometimes air 109 is blown for cooling the lamp.
[0006]
In any of the conventional oxidation heating apparatuses, oxygen is mainly used as a reaction gas. Oxygen does not decompose molecules even at the temperature usually used for oxidation (generally 700 to 800 ° C. or higher and 1100 ° C. or lower), so that there was no problem even if the gas temperature was high. Rather, attention was paid to how to keep the oxygen temperature high and uniform (see, for example, Patent Documents 1 and 2).
If a highly reactive gas is used, an oxide film having the same film quality as that of the related art can be formed while lowering the temperature of the substrate. However, an active gas is self-decomposed at a high temperature used in the oxidation step. For example, ozone has an oxidizing power that is orders of magnitude higher than oxygen, but when it touches a wall heated to about 400 ° C., it easily decomposes and is decomposed into oxygen, losing its oxidation activity. Therefore, even if ozone gas is introduced into a conventional furnace in which the temperature of the gas-contacting furnace wall or the gas in the furnace becomes high, the ozone gas is self-decomposed and the original oxidation rate cannot be obtained.
[0007]
When the semiconductor substrate is heated and oxidized in an ozone atmosphere by a gas supply method as shown in FIG. 9, if the diameter of the semiconductor substrate exceeds 1 cm, the thickness of the oxide film formed on the surface of the semiconductor substrate becomes uneven. Was inevitable for the following reasons:
The reactor shown in FIG. 9 is provided with a conduit 200 at an upper part, an exhaust port 203 at a lower part, and a semiconductor substrate 202 arranged so as to be perpendicular to a gas flow from the conduit 200 to the exhaust port 203. Ozone is introduced into the housing 201 through the conduit 200, reacts with the surface of the semiconductor substrate 202, and is exhausted from the exhaust port 203. Looking at the gas flow, the center of the sample is more likely to be directly hit by the gas from the conduit, but the periphery is more exposed to gas flowing radially across the substrate surface. Ozone gas changes into oxygen when it reacts with the substrate, so that the ozone concentration around the substrate becomes lower than at the center. Therefore, the oxidation rate of the sample is large in the central part and small in the peripheral part.
[0008]
In order to eliminate the non-uniformity of the ozone concentration in the reaction furnace shown in FIG. 9, a reactor provided with a shower head 204 downstream of the upper opening is proposed in FIG. The shower head 204 has a structure in which a plurality of holes are provided in order to equalize the flow rate.
In the reaction furnace of FIG. 10, the ozone gas is supplied to the surface of the substrate a little more uniformly than in the method of FIG. 9 by passing through a plurality of holes of the shower head 204. However, this is only a problem of a degree, and the problem of the non-uniformity of the ozone concentration is basically solved by using a means for supplying gas from a plurality of holes called a conventional shower head shown in FIG. It has not been.
[0009]
That is, this shower head is still insufficient in terms of uniform supply. This is because the gas after contacting the semiconductor substrate is exhausted from one outlet 203, so that there is still an undesirable radial flow across the surface of the semiconductor substrate. Therefore, although this method is more effective than the method shown in FIG. 9, a decrease in the effective ozone concentration in the surrounding area cannot be avoided.
Further, the semiconductor substrate is kept at a high temperature of about 700 ° C. or more for oxidation. Therefore, when the shower head 204 and the reaction gas pipe to the shower head 204 are close to the semiconductor substrate, they are heated by radiant heat. Therefore, the supplied ozone gas touches the heated shower head 204 and the inner wall of the reaction gas pipe to be decomposed, and the effective concentration of ozone reaching the semiconductor substrate surface decreases.
[Patent Document 1]
JP 2000-31077 A
[Patent Document 2]
JP 2000-200758 A
[0010]
[Problems to be solved by the invention]
In the above-described conventional heating furnace, when a semiconductor substrate is heated in a reactive gas atmosphere such as ozone, the reactive gas comes into contact with a heated portion other than the semiconductor substrate surface and self-decomposes, thereby reducing the reactivity. There was a problem of doing it.
In addition, when the semiconductor substrate has a large area, the reactive gas flows along the surface of the semiconductor substrate, and the reactive gas gradually decomposes on the substrate surface. However, there is a problem that the uniform supply of the reaction gas onto the semiconductor substrate is hindered.
In view of the above problems, the object of the present invention is to suppress the reaction gas from being heated and decomposed outside the semiconductor substrate, and the concentration of the reaction gas reacting with the surface of the semiconductor substrate becomes substantially equal on all surfaces. It is an object of the present invention to provide a semiconductor heat treatment apparatus.
[0011]
[Means for Solving the Problems]
The present invention employs the following solution in order to achieve the above object.
(1) In a shower head that supplies and exhausts a reactive gas at a uniform concentration to the surface of a semiconductor substrate, gas shower and exhaust units including a reactive gas supply hole and a reactive gas exhaust hole are provided in the shower head at equal intervals. A cooling means provided in the shower head, a supply gas accumulation region and an exhaust gas accumulation region in the shower head, the supply gas accumulation region and the reaction gas supply hole being connected by a supply thin tube, and the exhaust gas being exhausted by an exhaust thin tube. A gas storage region and the reaction gas exhaust hole are connected.
(2) In the shower head according to the above (1), the gas suction / exhaust unit is configured such that the reaction gas supply holes and the reaction gas exhaust holes are alternately arranged in the length direction of the shower head. The showerhead according to claim 1.
(3) In the shower head according to the above (1), the gas suction / exhaust unit is provided with the reaction gas exhaust hole so as to surround the reaction gas supply hole.
[0012]
(4) In the shower head according to (3), the gas suction / exhaust unit forms a hexagon in units of a pair of supply hole exhaust holes provided with the reaction gas exhaust holes so as to surround the reaction gas supply holes. And the hexagons are arranged concentrically and evenly.
(5) In a shower head that supplies and exhausts a reactive gas at a uniform concentration to the surface of a semiconductor substrate, gas shower and exhaust units including a reactive gas supply hole and a reactive gas exhaust hole are provided at equal intervals in the shower head. A cooling means provided in the shower head, a supply gas storage region and an exhaust gas storage region provided in the shower head, the supply gas storage region and the reaction gas supply hole being connected by a supply thin tube, and exhaust gas being connected by an exhaust thin tube. Connecting a storage gas region with the reaction gas exhaust hole, a reaction gas supply pipe communicating with the supply gas storage region, a reaction gas discharge tube communicating with the exhaust gas storage region, and cooling means for cooling the reaction gas supply tube. It is characterized by having been provided.
[0013]
(6) In the shower head according to the above (5), the gas suction / exhaust unit is configured such that the reaction gas supply holes and the reaction gas exhaust holes are alternately arranged in a length direction of the shower head. I do.
(7) In the shower head according to (5), the gas suction / exhaust unit is provided with the reaction gas exhaust hole so as to surround the reaction gas supply hole.
(8) In the shower head according to the above (7), the gas suction / exhaust unit forms a hexagon with a supply hole exhaust hole pair provided with the reaction gas exhaust hole so as to surround the reaction gas supply hole as a unit. And the hexagons are arranged concentrically and evenly.
[0014]
(9) In a semiconductor heat treatment apparatus, an apparatus for heating a semiconductor substrate surface while supplying a reactive gas at a uniform concentration, using an oxidizing gas containing ozone as the reactive gas and mounting the semiconductor substrate. 9. A jig, a housing for accommodating the semiconductor substrate mounted on the jig to form a reaction chamber, and a reactive gas supplied to the surface of the semiconductor substrate in the housing and exhausting the reaction gas. 5. A shower head according to any one of claims 1 to 3, a control means for controlling a supply amount of a reactive gas inside the housing, and a heat source for heating the semiconductor substrate.
(10) In the semiconductor heat treatment apparatus according to (9), a sealed space is formed by the jig, the housing, and the shower head, a semiconductor substrate is installed in the sealed space, and the reactant gas is supplied to the sealed space. A hole and the reaction gas exhaust hole are provided.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiments of the present invention will be described below in detail with reference to the drawings.
(First embodiment)
FIG. 1 shows a lamp heating type reactive gas heat treatment apparatus according to a first embodiment of the present invention.
FIG. 1A is a sectional view of a lamp heating type reactive gas heat treatment apparatus, and FIG. 1B is a view showing a lower outer surface of a shower head 90 indicated by “｛” in the figure.
The oxidation furnace shown in FIG. 1 is roughly composed of a shower head 90 serving as an ozone gas-contacting portion and a heater chamber housing 91 constituting a housing. The shower head 90 and the heater chamber housing 91 are made of metal to increase the cooling capacity. , For example, is formed of an aluminum alloy.
In addition, a flow passage 80 serving as a cooling means is provided inside, and a portion where the ozone gas comes into contact with the cooling liquid through the flow passage 80 is 0 ° C. or less.
The present embodiment is characterized in that the reaction gas supply pipe for supplying the ozone gas to the shower head is not heated, so that it is not necessary to cool the pipe.
The shower head 90 is separated into two chambers, a supply gas accumulation area 34 and an exhaust gas accumulation area 37, by a partition wall 40 provided in the length direction. The respective areas 34 and 37 are an intake pipe and an exhaust pipe for circulating the ozone gas 4. Is connected to the outside of the shower head 90. As shown in FIG. 1B, the bottom surface of the shower head 90 is provided with a plurality of holes 42 and 43 continuously penetrating the wall in the length direction. The hole 42 communicates with the supply gas accumulation region 34. The hole 43 communicates with the exhaust gas accumulation region 37.
[0016]
The effects of the supply gas accumulation region 34 and the exhaust gas accumulation region 37 are to make the amount of ozone supplied from the plurality of intake narrow tubes 35 uniform and to make the amount of exhaust gas uniform by the plurality of exhaust narrow tubes 36. This is due to the fact that the conductance of these accumulation regions is greater than the conductance of the capillaries, so that the inlet and outlet pressures of all capillaries are equal. A flow passage 80 is provided between the hole 42 and the hole 43 of the shower head 90 as illustrated. A cooling medium such as ethanol is circulated through the flow passage 80, for example. By flowing the cooling medium through the flow passage 80 in this manner, the temperature of the corresponding portion of the shower head that is in contact with the ozone gas, which is the reaction gas, becomes 0 ° C. or less. In this example, the material of the ozone gas contact portion is an aluminum alloy.
On the other hand, the heater chamber housing 91 is formed in a concave shape with one side opened, and is configured to cover the holes 42 and 43 of the shower head 90 in a sealed state. On the opening side of the heater chamber housing 91, a quartz boat 2 having a support table is mounted. A semiconductor substrate 1 is provided on a support of the quartz boat 2. The heater chamber is airtight and no reactive gas enters.
[0017]
The semiconductor substrate 1 can be made of a semiconductor as a whole, a substrate in which a semiconductor is deposited on a glass plate, or a silicon base material.
A plurality of lamps 9 for heating the semiconductor substrate 1 are arranged along the semiconductor substrate 1 in a space between the concave portion defined by the step of the heater chamber housing 91 and the quartz boat 2. . Since the lamp 9 is disposed in the space, the light of the lamp 9 does not directly irradiate the shower head 90.
A flow controller 5 is provided at a supply port to the supply gas accumulation region 34. In the space where the semiconductor substrate 1 is arranged, the measuring end of the pressure gauge 31 is exposed so as to be measurable. A radiation thermometer 30 is provided to measure a radiation temperature near the center of the semiconductor substrate 1 based on the lamp 9.
The control device 13 controls the lamp 9 and the flow controller 5 based on the measured pressure of the pressure gauge 31 and the measured temperature of the radiation thermometer 30 as follows.
[0018]
First, the flow rate of the ozone gas 4 is controlled by the flow rate controller 5. The flow of the ozone gas passes through the supply gas accumulation region 34 and the hole 42 and is sprayed on the semiconductor substrate surface 1 in the reaction gas reaction region 41, and then is exhausted through the hole 43 of the shower head 90 and the exhaust gas accumulation region 37. Exhausted from mouth. At that time, a reaction region is defined by the quartz boat 2 and the bottom surface of the shower head 90. The pressure of ozone 4 supplied to the reaction zone is adjusted by a flow controller 5. Thereby, the pressure is adjusted to 20 hPa or less, preferably 10 hPa or less, more preferably 5 hPa or less in the supply gas reaction region in the shower head 7. The pressure and flow rate of the ozone 4 are designed to be adjusted by the diameter of the reaction gas supply port and the reaction gas discharge port of the shower head 7 and their numbers. The temperature is controlled as follows. The semiconductor substrate 1 is heated by infrared rays from the lamp 9. At this time, the temperature of the semiconductor substrate 1 is measured at any time during the heating by the radiation thermometer 30, and the input power of the lamp 9 is controlled by the control device 13 based on the detected temperature of the radiation thermometer 30, and the temperature of the semiconductor substrate 1 is reduced. Keep at the set value.
The control device 13 constantly monitors the pressure and the temperature during the heating, controls the pressure so as to be an optimum pressure at each temperature, and gives a warning in the above state such as abnormal combustion of ozone.
[0019]
(Second embodiment)
A second embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 2 shows a second embodiment of the present invention, and is a configuration diagram of an oxidation furnace (lamp heating type reactive gas heat treatment apparatus) using ozone as a reaction gas according to the present invention.
The oxidation furnace shown in FIG. 2 includes a semiconductor substrate 1, a quartz boat 2 having a support, a quartz tube 3, a flow controller 5, a double quartz tube 6, a showerhead 7, a nitrogen exhaust tube 8, and a halogen lamp 9. , An ozone exhaust pipe 11, a purging port 20 of the housing, a radiation thermometer 30, a pressure measurement meter 31, and a control device 13 for controlling the halogen lamp 9 based on the measurement values of the radiation thermometer 30.
In the furnace, a quartz boat 2 on which a semiconductor substrate 1 is mounted is arranged, a shower head 7 is arranged so as to house the semiconductor substrate 1, and a quartz pipe is inserted to introduce ozone gas into the shower head 7. And a halogen lamp 9 is provided along the furnace wall. The housing 14 has a shape corresponding to the outer shape of the shower head 7 and has a shape in close contact with the shower head 7. The housing 14 is configured to house the semiconductor substrate. The reaction gas ejected from the shower head 7 is directed by the housing so as to strike the semiconductor substrate.
[0020]
The features of the present invention as compared with the conventional furnace are that the ozone gas 4 is used, a structure in which the ozone gas comes into contact (shower head and ozone supply pipe) is cooled, and the ozone gas is uniformly applied to the surface of the semiconductor substrate. That is, a shower head for irradiation is provided. These are described in detail below.
First, the cooling structure will be described.
In FIG. 2, the tube 3 and the shower head 7 constituting the cooling means are formed of a material (for example, quartz or the like) which does not easily absorb the infrared light of the halogen lamp 9. Therefore, it is difficult to be heated.
[0021]
Further, the outer wall of the double tube 6 made of quartz, which transports ozone and the shower head, which is an ozone gas contact portion, is cooled with nitrogen. That is, the cooling nitrogen gas 10 passes through the shower head 7 through the quartz double pipe 6 and is discharged from the exhaust pipe 11, thereby cooling the inner pipe wall of the double pipe 6 and the shower head outer wall. Here, since the self-decomposition rate is suppressed to 1/50 or less only by cooling ozone 4 from 60 ° C. to 0 ° C., it is desirable to keep the gas contact portion as low as possible. Therefore, the effect of cooling the nitrogen gas 10 is effective for increasing the cooling efficiency of the gas contact portion and suppressing self-decomposition of ozone. The temperature of the cooling nitrogen gas is 0 ° C. or lower, more preferably -60 ° C. or lower. The lower limit is -160C.
After the nitrogen gas used for cooling is exhausted from the exhaust pipe 11, it is reused through a purifier (not shown). This allows efficient use of the cooling gas. In addition, compared to the case where air in a clean room is used as a cooling gas, impurities contained in the cooling gas can be reduced to a ppb level or less, so that the inside of the quartz double tube 6 and the showerhead 7 is contaminated. The possibility that the substrate 1 is contaminated can be eliminated.
[0022]
The material of the quartz tube 3 is desirably synthetic quartz, and more desirably anhydrous synthetic quartz that does not easily absorb the infrared rays of the lamp 9. As the cooling gas, it is of course possible to use a gas other than nitrogen or a liquid such as water.
The ozone gas 4 is controlled by a flow controller 5 and passed through a quartz double tube 6 to a shower head 7. The ozone gas sent to the shower head 7 is blown onto the semiconductor substrate surface 1 from the bottom of the shower head 7 and then exhausted from an exhaust port at the bottom of the shower head 7. At this time, the ozone gas 4 is supplied to the semiconductor substrate 1 by the housing 14 defining the reaction region, and is finally forcibly exhausted from the exhaust pipe 8. The operation of the control device 13 is the same as in the first embodiment.
Although not shown, the installation mechanism of the semiconductor substrate 1 is for vertically driving the support on which the semiconductor substrate 1 is placed.
[0023]
(Third embodiment)
FIG. 3 shows a heater heating type reactive gas heat treatment apparatus according to a third embodiment of the present invention. FIG. 3 shows an oxidation furnace of a heater heating system in which a heater 12 is used as a heating source and the heater 12 is brought into direct contact with the semiconductor substrate 1 to heat it. Since the heater 12 is used, the temperature controllability is excellent, but rapid heating such as lamp heating is difficult. Therefore, it is necessary for process control to switch ozone to an inert gas such as nitrogen as soon as the ozone oxidation step is completed to suppress the progress of oxidation.
In the configuration of FIG. 3, the same components as those of the embodiment using the lamp 9 of FIG.
(Fourth embodiment)
FIG. 4 is a configuration diagram showing the vicinity of a shower head according to a fourth embodiment of the present invention.
The shower head includes an outer tube 38, an inner tube 38, a supply thin tube 35, and an exhaust thin tube 36, and includes a supply gas accumulation region 34 and an exhaust gas accumulation region 37 inside. The ozone gas 4 flows inside the inner cylinder, and the cooling nitrogen gas 10 flows inside the outer cylinder constituting the cooling means.
[0024]
The supply gas reaction region 41 is a region surrounded by the housing 44, the semiconductor substrate 1, and the outer container 38. The semiconductor substrate 1 is mounted on support tables 51, 51 'on a quartz board 2 constituting a jig. The semiconductor substrate 1 is surrounded by a housing 44 and is sealed by the housing 44, the outer cylinder 38 and the quartz board 2.
A cooling gas supply pipe 33 is provided on one outer end plate 47 of the outer cylinder 38, and a cooling gas exhaust pipe 45 is provided on the other outer end plate 49 of the outer cylinder 38.
The inner cylinder 39 has a smaller diameter than the outer cylinder 38 and is provided inside the outer cylinder 38. The reaction gas supply pipe 32 inserted into the cooling gas supply pipe 33 is provided on one inner end plate 48 of the inner cylinder 39, and the end plate 49 is provided on the other outer end plate 50 of the inner cylinder 39. A reaction gas exhaust pipe 46 is provided so as to penetrate through.
[0025]
The supply gas accumulation region 34 and the exhaust gas accumulation region 37 are provided in the inner cylinder 39. The supply gas storage area 34 is in communication with the reaction gas supply pipe 32, and the exhaust gas storage area 37 is in communication with the reaction gas exhaust pipe 46. The supply gas accumulation region 34 and the exhaust gas accumulation region 37 are separated by a partition wall 40. The supply thin tube 35 has one opening provided on the side of the partition 40 in contact with the supply gas accumulation region 34 of the inner cylinder 39 and the other opening provided in the supply gas reaction region 41.
Further, the exhaust thin tube 36 has one opening provided on the side of the partition wall 40 in contact with the exhaust gas accumulation region 37 and the other opening provided in the supply gas reaction region 41.
Further, the supply thin tubes 35 and the exhaust thin tubes 36 are provided alternately on the side of the outer container 38 that contacts the supply gas reaction region 41.
[0026]
The flow path of the ozone gas 4 is introduced from the reaction gas supply pipe 32, passes through the supply gas accumulation area 34, is guided from the reaction gas supply hole 42 to the supply gas reaction area 41, and is supplied to the semiconductor substrate 1. Thereafter, the gas passes through the reaction gas exhaust hole 43 arranged around the reaction gas supply hole 42, passes through the exhaust gas accumulation region 37, and is discharged from the reaction gas exhaust pipe 46 to the outside of the chamber.
Although a plurality of openings 62 of the supply thin tube 35 are provided, the uniformity of the ozone gas pressure can be maintained as long as the conductance in the supply gas accumulation region 34 is sufficiently larger than the conductance of the supply thin tube. Similarly, the pressure uniformity at the opening 63 of the exhaust pipe 36 is maintained by the exhaust gas accumulation region 37 acting as a buffer. This is the same effect as in the first embodiment.
The nitrogen gas 10 serving as the cooling gas is supplied from the cooling gas supply pipe 33, flows between the outer cylinder 38 and the inner cylinder 39, and is discharged from the cooling gas exhaust pipe 45 to the outside of the chamber. At this time, the cooling gas flows around the bottom of the shower head, around the supply thin tube 35 and the exhaust thin tube 36 provided between the outer tube 38 and the inner tube 39, and cools them.
[0027]
In summary, the suppression of gas flow along the semiconductor substrate, the uniform input pressure over the entire surface of the semiconductor substrate, and the uniform exhaust back pressure make the ozone supply rate equivalent at any location on the semiconductor substrate. In addition, the growth rate of the formed oxide film becomes uniform. In addition, the cooling structure can suppress the thermal decomposition of the ozone gas during the transportation to the substrate.
Further, the supply and exhaust of the ozone gas are equally performed at any point on the semiconductor substrate. In other words, by repeating the gas intake / exhaust unit of the supply port and the exhaust port, the same gas is supplied and discharged at any location on the large-area substrate, so that a uniform large-area film can be formed. In addition, by repeating the gas intake / exhaust unit, it is possible in principle to cope with film formation on an arbitrary large-area substrate.
[0028]
FIG. 4 is a schematic diagram for the purpose of explanation, and the gas intake / exhaust unit of the reaction gas supply hole 42 and the reaction gas exhaust hole 43 can be optimized by their mutual combination structure.
FIG. 5 is a configuration diagram around another shower head section according to a fifth embodiment of the present invention. In the embodiment of FIG. 5, the configuration of the reaction gas exhaust hole 43 is different from the independent hole of the embodiment of FIG. 4 in that a hole provided concentrically around the reaction gas supply hole 42 as shown in FIG. Has been changed. The other configuration is not changed, and the description is omitted.
FIG. 6 shows an arrangement example of the gas intake and exhaust units in FIG. The arrangement of the supply hole exhaust hole pair viewed from the bottom of the shower head is such that the distance to the adjacent hole pair center position is uniform, that is, the center of a pair of holes around the center of a pair of holes. The position is a regular hexagon. This is an example, and other arrangement structures can be adopted. The point is that the ozone gas supply and exhaust may be arranged so as to be equivalent at any position on the semiconductor substrate.
[0029]
【The invention's effect】
When the semiconductor substrate is subjected to heat treatment in a reactive gas, the flow rate of the reactive gas to be brought into contact with the substrate surface is equalized in all parts of the substrate surface even when the semiconductor substrate has a large area. Heat treatment can be performed at a lower temperature than before, or heat treatment time can be shorter than before, at the same temperature as before, and a uniform film can be formed on all parts of a large-area substrate in order to maximize the activity of it can.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a lamp heating type reactive gas heat treatment apparatus according to a first embodiment of the present invention.
FIG. 2 is a configuration diagram of a lamp heating type reactive gas heat treatment apparatus according to a second embodiment of the present invention.
FIG. 3 is a configuration diagram of a heater heating type reactive gas heat treatment apparatus according to a third embodiment of the present invention.
FIG. 4 is a configuration diagram showing the vicinity of a shower head according to a fourth embodiment of the present invention.
FIG. 5 is a configuration diagram around another shower head section according to a fifth embodiment of the present invention.
FIG. 6 is an arrangement diagram of a reactive gas inlet / outlet pair at the bottom of the shower head in FIG. 5;
FIG. 7 is a configuration diagram of a conventional diffusion furnace using thermal radiation.
FIG. 8 is a configuration diagram of a conventional RTP device using a lamp as a heat source.
FIG. 9 is a configuration diagram of a conventional heat treatment apparatus having one reactive gas supply source.
FIG. 10 is a configuration diagram of a conventional heat treatment apparatus in which a reactive gas supply source has a shower head and has one exhaust port.
[Explanation of symbols]
1 semiconductor substrate
2 boats
3 tubes
4 Ozone gas
5 Flow controller
6 Double tube made of quartz
7 shower head
8 Nitrogen exhaust pipe
9 Halogen lamp
10 Nitrogen gas
11 Ozone exhaust pipe
12 heater
13 Control device
14 Housing
20 Dedicated port for purging
30 Heat radiation thermometer
31 Pressure gauge
32 Reaction gas supply pipe
33 Cooling gas supply pipe
34 Supply gas storage area
35 Supply capillary
36 Exhaust capillary
37 Exhaust gas accumulation area
38 outer cylinder
39 inner cylinder
40 partition
41 Supply gas reaction area
42 Reaction gas supply hole
43, 43 'Reactive gas exhaust hole
44 Side wall
45 Cooling gas exhaust pipe
46 Reactive gas exhaust pipe
47, 49 Outer end plate
48, 50 inner end plate
51, 51 'substrate support
80 Coolant
90 shower head
91 Heater room housing
200 Conduit 200
201 housing
202 Semiconductor substrate
203 exhaust port
204 shower head

Claims (10)

In a shower head for supplying and exhausting a reactive gas at a uniform concentration to a semiconductor substrate surface, a gas suction / exhaust unit including a reactive gas supply hole and a reactive gas exhaust hole is provided at equal intervals in the shower head, A cooling means is provided in the head, and a supply gas accumulation region and an exhaust gas accumulation region are provided in the shower head,
A shower head, wherein the supply gas storage region and the reaction gas supply hole are connected by a supply thin tube, and the exhaust gas storage region and the reaction gas exhaust hole are connected by an exhaust thin tube. 2. The shower head according to claim 1, wherein the gas suction / exhaust unit has a structure in which the reaction gas supply holes and the reaction gas exhaust holes are alternately arranged in a length direction of the shower head. 2. The shower head according to claim 1, wherein the gas intake / exhaust unit is provided with the reaction gas exhaust hole so as to surround the reaction gas supply hole. The gas suction / exhaust unit is arranged so as to form a hexagon in units of a supply hole exhaust hole pair provided with the reaction gas exhaust hole so as to surround the reaction gas supply hole, and the hexagon is evenly concentrically formed. The shower head according to claim 3, wherein the shower head is arranged. In a shower head for supplying and exhausting a reactive gas at a uniform concentration to a semiconductor substrate surface, a gas suction / exhaust unit including a reactive gas supply hole and a reactive gas exhaust hole is provided at equal intervals in the shower head, A cooling means is provided in the head, and a supply gas accumulation region and an exhaust gas accumulation region are provided in the shower head,
A supply thin tube connects the supply gas accumulation region and the reaction gas supply hole, an exhaust narrow tube connects an exhaust gas accumulation region and the reaction gas exhaust hole, and the reaction gas supply tube communicates with the supply gas accumulation region, and a reaction gas exhaust is provided. A shower head, wherein the pipe communicates with the exhaust gas accumulation area and a cooling means for cooling the reaction gas supply pipe is provided. 6. The shower head according to claim 5, wherein the gas suction / exhaust unit has the reaction gas supply holes and the reaction gas exhaust holes alternately arranged in a length direction of the shower head. The shower head according to claim 5, wherein the gas suction / exhaust unit is provided with the reaction gas exhaust hole so as to surround the reaction gas supply hole. The gas suction / exhaust unit is arranged so as to form a hexagon in units of a supply hole exhaust hole pair provided with the reaction gas exhaust hole so as to surround the reaction gas supply hole, and the hexagon is uniformly concentrically formed. The shower head according to claim 7, wherein the shower head is disposed at a position where the shower head is located. An apparatus for heating while supplying a reactive gas at a uniform concentration to a semiconductor substrate surface, using an oxidizing gas containing ozone as a reactive gas, a jig for mounting a semiconductor substrate, and a jig mounted on the jig. The shower according to any one of claims 1 to 8, wherein the semiconductor substrate accommodates the semiconductor substrate and forms a reaction chamber, and the reactive gas is supplied and exhausted to the surface of the semiconductor substrate in the housing. A semiconductor heat treatment apparatus comprising: a head; control means for controlling a supply amount of a reactive gas inside a housing; and a heat source for heating the semiconductor substrate. A sealed space is formed by the jig, the housing, and the shower head, a semiconductor substrate is installed in the sealed space, and the reaction gas supply hole and the reaction gas exhaust hole are provided in the sealed space. The semiconductor heat treatment apparatus according to claim 9.

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