JP4138269B2 - Semiconductor manufacturing equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a semiconductor manufacturing apparatus , and more particularly to a semiconductor manufacturing apparatus that forms a thin film on a silicon substrate.
[0002]
[Prior art]
The prior art will be described with reference to FIGS.
FIG. 5A is a cross-sectional view of the reaction chamber portion of the conventional film forming apparatus as viewed from above, and FIG. 5B is a vertical cross-sectional view taken along the line DD in FIG. FIG. 6 is a diagram showing a process temperature in a conventional film forming apparatus.
Inside the reaction tube 1, a boat 16 is provided on which a plurality of substrates to be processed 2 can be placed in multiple stages at the same interval.
A shaft 161 at the lower end of the boat 16 has a structure that penetrates the shutter 23 in a rotatable and airtight manner.
The rotating part 22 is kept airtight with a magnetic seal or the like.
The boat 16 is moved up and down by an elevator mechanism (not shown) so that it can be taken in and out of the reaction tube 1. In addition, a rotation drive unit (not shown) for rotating the boat 16 is provided to improve the processing uniformity of the substrate 2 to be processed.
When the boat 16 is raised to the upper limit, the shutter 23 is connected to the flange 3 in an airtight manner.
The plurality of substrates to be processed 2 placed on the boat 16 in multiple stages are heated to a predetermined temperature by the heater 10 together with the boat 16 and the reaction tube 1.
The reaction gas is introduced into the reaction tube 1 from the gas introduction tube 17, and the gas in the reaction tube 1 is exhausted from the exhaust tube 18.
[0003]
Next, the operation will be described.
After the plurality of substrates to be processed 2 are placed on the boat 16 with the boat 16 lowered by an elevator mechanism (not shown), the boat 16 is raised and inserted into the reaction tube 1.
At this time, the flange 3 and the shutter 23 are connected so as to maintain airtightness, and the inside of the reaction tube 1 is exhausted from the exhaust pipe 18 by a pump (not shown), and at the same time, hydrogen (H ₂ ) is introduced to Replace the gas with hydrogen.
Thereafter, the heater 10 is turned on to heat the reaction tube 1 and the boat 16 inside, the substrate 2 to be processed, etc. to 700 ° C.
When the temperature of each part inside the reaction tube 1 reaches 700 ° C., the boat 16 is rotated while hydrogen is introduced to remove and clean the natural oxide film on the surface of the substrate to be processed.
After this treatment is performed for about 30 minutes, the temperature inside the reaction tube 1 is lowered to 500 ° C., and when the temperature inside the reaction tube 1 is stabilized, monogermane (GeH ₄ ) and monosilane (SiH ₄ ) are introduced from the gas introduction tube 17. Then, silicon germanium (SiGe) is deposited.
The pressure inside the reaction tube 1 is adjusted by a pressure adjusting mechanism (not shown) provided on the downstream side of the exhaust pipe 18.
[0004]
In this conventional film forming apparatus, as shown in the film forming sequence of FIG. 6, it takes 230 minutes from the start of heating of the reaction tube 1 to the end of the temperature reduction after finishing the processing.
As can be seen from this film-forming sequence, the temperature of the reaction tube 1 to be raised or lowered is long, so that the processing speed (throughput) of the substrate to be processed as an apparatus is lowered. For this reason, it becomes a subject to shorten the temperature raising / lowering time of the reaction tube 1 and to improve the processing speed (throughput).
[0005]
[Problems to be solved by the invention]
As described above, since the pretreatment and the temperature at the time of film formation are different, it takes a long time to heat and cool the reaction tube, resulting in a decrease in throughput. Therefore, it is required to reduce the temperature difference between the pretreatment and the film formation, shorten the temperature raising / lowering time of the reaction tube 1, and improve the processing speed (throughput).
[0006]
[Means for Solving the Problems]
According to a first aspect of the invention,
A reaction chamber for stacking and accommodating substrates;
A heating means provided outside the reaction chamber for heating the atmosphere in the reaction chamber;
Gas supply means for supplying a plurality of desired gases into the reaction chamber;
A remote plasma mechanism;
Exhaust means for exhausting the atmosphere in the reaction chamber;
A semiconductor manufacturing apparatus for growing a single crystal silicon film on the surface of the substrate,
The remote plasma mechanism is
Two electrodes covered with a dielectric protective tube and applied with high frequency power;
A shield provided via an insulator at the end of the electrode,
The gas supply means includes
A hydrogen gas introduction pipe for supplying hydrogen gas into the reaction chamber;
Anda different said source gas inlet pipe and the hydrogen gas inlet pipe a source gas inlet pipe for supplying a raw material gas into the reaction chamber,
The hydrogen gas inlet pipe is formed of a dielectric material, is erected in the stacking direction of the substrate, a semiconductor manufacturing device comprising a call having a plurality of gas supply holes in the stacking direction of said substrate.
[0007]
Thus, hydrogen used for pretreatment is activated by the remote plasma mechanism, and the substrate to be processed can be cleaned at a low temperature. As a result, the temperature of the pretreatment and the temperature of the single crystal growth performed later in the same reaction chamber can be made the same, so the time for raising the temperature to a temperature higher than the single crystal growth temperature necessary for the pretreatment, The time required for the temperature to be lowered to the single crystal growth temperature can be omitted, and the processing speed (throughput) can be improved accordingly. Note that in the pretreatment of the surface of the substrate to be processed using active species of hydrogen generated by remote plasma, impurities such as a natural oxide film on the surface of the substrate to be processed are removed.
[0008]
According to the second aspect of the present invention,
A reaction chamber for stacking and accommodating substrates;
A heating means provided outside the reaction chamber for heating the atmosphere in the reaction chamber;
Gas supply means for supplying a plurality of desired gases into the reaction chamber;
A remote plasma mechanism;
Exhaust means for exhausting the atmosphere in the reaction chamber;
A semiconductor manufacturing apparatus for forming a silicon germanium film on the substrate surface,
The remote plasma mechanism is
Two electrodes covered with a dielectric protective tube and applied with high frequency power;
A shield provided via an insulator at the end of the electrode,
The gas supply means includes
A hydrogen gas introduction pipe disposed between the two electrodes and supplying hydrogen gas into the reaction chamber;
Anda different said source gas inlet pipe and a raw material gas introduction pipe for supplying monosilane and monogermane the hydrogen gas inlet tube into the reaction chamber,
The hydrogen gas inlet pipe is formed of a dielectric material, is erected in the stacking direction of the substrate, a semiconductor manufacturing device comprising a call having a plurality of gas supply holes in the stacking direction of said substrate.
[0009]
Thus, hydrogen used for pretreatment is activated by the remote plasma mechanism, and the substrate to be processed can be cleaned at a low temperature. As a result, the temperature of the pretreatment and the formation temperature of the silicon germanium film performed at a temperature of 700 ° C. or lower in the same reaction chamber can be made the same. Therefore, the formation temperature of the silicon germanium film necessary for the pretreatment can be increased. The time for raising the temperature to a high temperature and the time for lowering the temperature to form the silicon germanium film can be omitted, and the processing speed (throughput) can be improved accordingly. Note that in the pretreatment of the surface of the substrate to be processed using active species of hydrogen generated by remote plasma, impurities such as a natural oxide film on the surface of the substrate to be processed are removed.
[0010]
Preferably, the reaction chamber wall is made of a dielectric material such as quartz, and a hot wall structure is used in which the temperature of the reaction chamber wall and the substrate in the reaction chamber is heated by a heater disposed outside the reaction chamber.
[0011]
The semiconductor manufacturing apparatus of the present invention has a structure in which two or more substrates to be processed are stacked and placed in a reaction chamber for processing.
[0012]
Preferably, the substrate is a silicon wafer, and the semiconductor to be single-crystallized is silicon (Si) or silicon germanium (SiGe).
[0013]
When forming the silicon germanium (SiGe) film, the source gases supplied to the reaction chamber in a reduced pressure state are preferably monogermane (GeH ₄ ) and monosilane (SiH ₄ ).
[0014]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described with reference to FIGS. 1, 2, 3, and 4.
[0015]
(First embodiment)
FIG. 1A is a cross-sectional view seen from above the reaction chamber portion of the present embodiment, and FIG. 1B shows a vertical cross-sectional view taken along line AA in FIG.
2 is a cross-sectional view of the cross section of FIG. 1, FIG. 2 (A) is a cross-sectional view seen from above the reaction chamber portion of the present embodiment, and FIG. 2 (B) is FIG. The BB line longitudinal cross-sectional view of (A) is shown. Note that the heater 10 is omitted.
[0016]
Inside the reaction tube 1, a boat 16 is provided on which a plurality of substrates to be processed 2 can be placed in multiple stages at the same interval. The boat 16 can be taken in and out of the reaction tube 1 by an elevator mechanism (not shown).
The shaft 161 at the bottom of the boat 16 has a structure that penetrates the shutter 23 in a rotatable and airtight manner. The rotating unit 22 is kept airtight by a magnetic seal or the like, but may be a mechanism such as a magnet coupling.
Further, in order to improve the uniformity of processing, a rotation drive unit (not shown) for rotating the boat 16 is provided.
As shown in FIG. 1, the shutter 23 is airtightly connected to the flange 3 when the boat 16 is raised to the upper limit.
[0017]
Near the wall surface inside the reaction tube 1, two elongated conductive electrodes 5 are arranged as a plasma generation source so as to be covered with a dielectric protective tube 6, and an oscillator 12 emits at the electrode end 4 of the two electrodes. High-frequency power is applied via the matching unit 13.
A shield 9 is provided near the end of the electrode 5 via an insulator 8 to prevent discharge.
By this shield, the discharge inside the reaction tube 1 is limited to the vicinity of the substrate 2 to be processed.
The electrode end 4 passes through a metal flange 3 that is airtightly connected to the lower part of the reaction tube 1 and is drawn out of the reaction tube 1. The protection tube 6 includes the protection tube 6 and the flange 3. Since it is hermetically sealed, it is a space independent of the inside of the reaction tube 1 and is always at atmospheric pressure.
[0018]
Further, as shown in FIG. 2, a dielectric discharge tube 7 having a plurality of small holes 14 for gas blowing is provided in a space in the reaction tube 1 sandwiched between the electrodes 5 to process the substrate 2 to be processed. When introducing the hydrogen gas to be introduced into the reaction tube 1, the gas may pass through the small hole 14.
When a plasma 15 is generated by applying high-frequency power between two elongated electrodes 5 arranged side by side, active species of hydrogen generated in the plasma 15 pass through the small holes 14 and are supplied to the substrate 2 to be processed.
At this time, the structure of the discharge tube 7 and the size, number, position, etc. of the discharge tube 7 are optimized according to the purpose of processing in order to suppress the discharge of charged particles generated by the plasma 15 from the small hole 14. In the present embodiment, the position of the small hole 14 is set to be intermediate between the substrates to be processed 2.
As a result, the active species of hydrogen are evenly supplied to each substrate 2 on the boat 16.
Although the discharge tube 7 may not be provided, by limiting the plasma generation space with the discharge tube 7, it is possible to suppress the diffusion of charged particles from the plasma 15, and damage to the substrate 2 to be processed due to ions or the like. Can be reduced.
[0019]
Next, the operation will be described.
[0020]
After the boat 16 is lowered by an elevator mechanism (not shown) and a plurality of substrates 2 are placed on the boat 16, the boat 16 is raised and inserted into the reaction tube 1, and the inside of the reaction tube 1 is exhausted by a pump (not shown). Then, hydrogen gas is introduced to replace the gas such as nitrogen inside the reaction tube 1 with hydrogen.
[0021]
The heater 10 is turned on to heat the reaction tube 1, the boat 16 inside, the substrate 2 to be processed, etc. to 500 ° C. When the temperature of each part inside the reaction tube 1 reaches 500 ° C., hydrogen gas for cleaning the surface of the substrate 2 to be processed is introduced into the discharge tube 7 while rotating the boat 16.
The pressure inside the reaction tube 1 is adjusted by a pressure adjusting mechanism (not shown). When the pressure reaches a predetermined value, high-frequency power output from the oscillator 12 is supplied to the electrode end 4 via the matching unit 13.
As a result, plasma 15 is generated inside the discharge tube 7 and the introduced hydrogen is activated and supplied to the substrate 2 being rotated from the small holes 14 provided in the discharge tube 7.
Impurities such as a natural oxide film on the surface of the substrate to be processed 2 are removed mainly by activated hydrogen.
[0022]
When the removal of impurities such as a natural oxide film is completed, monogermane (GeH ₄ ) and monosilane (SiH ₄ ) are introduced from the gas introduction pipe 17 and silicon germanium (SiGe) is formed at 500 ° C. while adjusting the pressure.
The pressure inside the reaction tube 1 is adjusted by a pressure adjusting mechanism (not shown) provided on the downstream side of the exhaust pipe 18.
[0023]
As shown in the film forming sequence of FIG. 4, the time from the start of heating the reaction tube 1 to the end of the process until the temperature drop is finished is that the pretreatment temperature is set to 500 ° C., which is the same as the film forming temperature. The processing time which took 230 minutes in the conventional technique (see the broken line) is reduced to 155 minutes.
[0024]
(Second Embodiment)
FIG. 3 is a diagram showing a second embodiment of the present invention, in which the heater is omitted. FIG. 3A is a cross-sectional view seen from above the reaction chamber portion of the present embodiment, and FIG. 3B is a longitudinal cross-sectional view taken along the line CC in FIG.
[0025]
Inside the reaction tube 1 is provided a boat 16 on which a plurality of substrates to be processed 2 can be placed in multiple stages at the same interval, and the main structure is the same as in FIG.
[0026]
The flange 3 is provided with an active gas introduction pipe 19, which is configured to supply the active species of hydrogen generated by the remote plasma unit 24 from the active species introduction pipe 19 into the reaction tube 1.
As a plasma source of the remote plasma unit 24, an ICP (Inductively Coupled Plasma) type or a microwave type is suitable. The material of the discharge part of the remote plasma unit 24 is preferably quartz, alumina, sapphire or the like.
[0027]
Next, the operation will be described.
[0028]
After the boat 16 is lowered by an elevator mechanism (not shown) and the substrate 2 is placed on the boat 16, the boat 16 is raised and inserted into the reaction tube 1, and the inside of the reaction tube 1 is exhausted by a pump (not shown). And a gas such as nitrogen inside the reaction tube 1 is replaced with hydrogen. Hydrogen is introduced from the gas introduction pipe 21.
[0029]
The heater 10 is turned on to heat the reaction tube 1 and the boat 16 inside, the substrate 2 to be processed, etc. to 500 ° C.
[0030]
When the temperature of each part inside the reaction tube 1 reaches 500 ° C., the pressure inside the reaction tube 1 is adjusted by a pressure adjusting mechanism (not shown). When the temperature reaches a predetermined value, the remote plasma unit 24 is operated and the remote plasma unit 24 The generated active species of hydrogen are introduced into the reaction tube 1 through the active species introduction tube 19 to remove impurities such as a natural oxide film on the surface of the substrate 2 to be processed placed on the rotating boat 16.
[0031]
Subsequent film formation is the same as described above.
[0032]
In the first and second embodiments, an example in which a plurality of substrates to be processed are collectively processed has been described, but the same applies to an apparatus that processes each substrate one by one.
[0033]
According to the present invention, since the temperature for cleaning the surface of the substrate to be processed before film formation of SiGe or Si can be lowered as compared with the conventional one, it can be made the same as the film formation temperature. Since the temperature for cleaning the substrate to be processed before film formation is the same as the film formation temperature, the time for raising and lowering the temperature of the reaction tube can be omitted, so that the throughput of the apparatus is improved.
[0034]
【The invention's effect】
According to the present invention, the temperature of surface cleaning with hydrogen of the substrate to be processed can be lowered, and as a result, the time for raising and lowering the temperature for pretreatment can be omitted, thereby improving the throughput of the apparatus.
[Brief description of the drawings]
FIGS. 1A and 1B are views for explaining a film forming apparatus according to a first embodiment of the present invention, FIG. 1A being a cross-sectional view, and FIG. 1B being FIG. It is an AA line longitudinal cross-sectional view.
FIGS. 2A and 2B are diagrams for explaining a film forming apparatus according to a first embodiment of the present invention, FIG. 2A being a cross-sectional view, and FIG. 2B being FIG. It is a BB line longitudinal cross-sectional view.
FIGS. 3A and 3B are diagrams for explaining a film forming apparatus according to a second embodiment of the present invention, FIG. 3A being a cross-sectional view, and FIG. 3B being FIG. FIG.
FIG. 4 is a diagram illustrating a process time in the first embodiment of the present invention.
5A and 5B are diagrams for explaining a conventional film forming apparatus, in which FIG. 5A is a cross-sectional view, and FIG. 5B is a vertical cross-sectional view taken along line AA in FIG. 5A. .
FIG. 6 is a diagram for explaining a conventional process time.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Reaction tube 2 ... Substrate 3 ... Flange 4 ... Electrode end 5 ... Electrode 6 ... Protection tube 7 ... Discharge tube 8 ... Insulating material 9 ... Shield 10 ... Heater 12 ... Oscillator 13 ... Matching device 14 ... Small hole 15 ... Plasma 16 ... Boat 17 ... Gas introduction pipe 18 ... Exhaust pipe 19 ... Active species introduction pipe 21 ... Gas introduction pipe 22 ... Rotating section 23 ... Shutter 24 ... Remote plasma unit

Claims (2)

A reaction chamber for stacking and accommodating substrates;
A heating means provided outside the reaction chamber for heating the atmosphere in the reaction chamber;
Gas supply means for supplying a plurality of desired gases into the reaction chamber;
A remote plasma mechanism;
Exhaust means for exhausting the atmosphere in the reaction chamber;
A semiconductor manufacturing apparatus for growing a single crystal silicon film on the surface of the substrate,
The remote plasma mechanism is
Two electrodes covered with a dielectric protective tube and applied with high frequency power;
A shield provided via an insulator at the end of the electrode,
The gas supply means includes
A hydrogen gas introduction pipe disposed between the two electrodes and supplying hydrogen gas into the reaction chamber;
Anda different said source gas inlet pipe and the hydrogen gas inlet pipe a source gas inlet pipe for supplying a raw material gas into the reaction chamber,
2. The semiconductor manufacturing apparatus according to claim 1, wherein the hydrogen gas introduction pipe is made of a dielectric material, is erected in the substrate stacking direction, and has a plurality of gas supply holes in the substrate stacking direction . A reaction chamber for stacking and accommodating substrates;
A heating means provided outside the reaction chamber for heating the atmosphere in the reaction chamber;
Gas supply means for supplying a plurality of desired gases into the reaction chamber;
A remote plasma mechanism;
Exhaust means for exhausting the atmosphere in the reaction chamber;
A semiconductor manufacturing apparatus for forming a silicon germanium film on the substrate surface,
The remote plasma mechanism is
Two electrodes covered with a dielectric protective tube and applied with high frequency power;
A shield provided via an insulator at the end of the electrode,
The gas supply means includes
A hydrogen gas introduction pipe disposed between the two electrodes and supplying hydrogen gas into the reaction chamber;
Anda different said source gas inlet pipe and a raw material gas introduction pipe for supplying monosilane and monogermane the hydrogen gas inlet tube into the reaction chamber,
2. The semiconductor manufacturing apparatus according to claim 1, wherein the hydrogen gas introduction pipe is made of a dielectric material, is erected in the substrate stacking direction, and has a plurality of gas supply holes in the substrate stacking direction .

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