JP3948295B2 - Processing equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a pressurized KoSo location, and non contact mask processing means to particularly unnecessary resist mask is characterized in processing means using a micro-plasma source.
[0002]
[Prior art]
In general, a resist process is used when patterning is performed on an object typified by a substrate having a thin film formed on the surface. An example is shown in FIG. In FIG. 6, first, a photosensitive resist 26 is applied to the surface of the object to be processed 25 (a). Next, the resist 26 can be patterned into a desired shape by developing after exposure using an exposure machine (b). Then, the workpiece 25 is placed in a vacuum vessel, plasma is generated in the vacuum vessel, and the workpiece 25 is etched using the resist 26 as a mask, whereby the surface of the workpiece 25 is patterned into a desired shape. (C). Finally, the resist 26 is removed with oxygen plasma, an organic solvent, or the like, thereby completing the processing (d).
[0003]
Since the resist process as described above is suitable for accurately forming a fine pattern, it has played an important role in the manufacture of electronic devices such as semiconductors. In addition, there is a drawback that the process is complicated.
[0004]
Therefore, a new processing method that does not use a resist process has been studied. As an example, FIG. 7 shows a conceptual diagram of non-contact mask etching. An object to be processed 8 is placed on the electrode 7 disposed in the vacuum vessel 1, and while the gas is supplied from the gas supply device 2 into the vacuum vessel 1, the inside of the vacuum vessel 1 is evacuated by the exhaust device 3, and the vacuum is supplied. While controlling the inside of the container 1 to a predetermined pressure, high-frequency power is supplied from the high-frequency power source 4 for the plasma source to the coil 6 disposed on the dielectric plate 5 as the plasma source, thereby generating plasma in the vacuum container 1. This is a method of processing an object to be processed by causing active particles that are generated and leaked from plasma through a minute through hole provided in a mask 9 disposed in the vicinity of the object to be processed 8 to act on the object to be processed 8.
[0005]
As another example, FIG. 8 shows a conceptual diagram of microplasma etching. A high-frequency power is supplied to a microplasma source 17 that can be disposed in the vicinity of the workpiece 8 to generate microplasma, and active particles that leak from the microplasma act on the workpiece 8 to It is a method of processing.
[0006]
[Problems to be solved by the invention]
However, in the processing of the object to be processed described in the conventional example, there may be a problem that it is difficult to control the patterning shape formed on the surface of the object to be processed. As a result, there is a problem that processing accuracy is lowered.
[0007]
The present invention is the light of the conventional problems, it can be controlled patterned shape, and has an object to provide an excellent pressure KoSo location processing accuracy.
[0008]
[Means for Solving the Problems]
The processing apparatus of the present invention includes a vacuum vessel, a gas supply device for supplying gas into the vacuum vessel, an exhaust device for exhausting the vacuum vessel, a plasma source for generating plasma in the vacuum vessel, a high frequency power supply for supplying high frequency power to the plasma source, wherein the electrodes disposed in a vacuum container, is between and is arranged to face the electrode Rutotomoni penetrations holes between the electrode and the plasma source is provided a mask, a distance measuring device for measuring by a laser a distance between the object to be processed and the mask disposed on the electrode surface provided opposite to the vacuum vessel and the electrode, resulting in the distance measuring device And a distance control device that changes a distance between the mask and the object to be processed based on the obtained information.
[0009]
In the processing apparatus of the present gun onset bright, preferably, the distance control device is preferably operable without stopping the plasma generated in the vacuum chamber. It is also desirable to gradually increase the distance between the mask and the object to be processed. Alternatively, the distance between the mask and the object to be processed may be gradually reduced.
[0010]
Preferably, the mask is a conductor and a negative DC voltage is applied to the mask. Alternatively, the mask may be a conductor and high frequency power may be applied to the mask. Alternatively, the mask may be a conductor in which an insulator is coated, and high frequency power may be applied to the mask. Alternatively, it may be applied to high-frequency power to that electrodes be placed an object to be processed.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 to 3.
[0023]
FIG. 1 shows a cross-sectional view of a processing apparatus equipped with an inductively coupled plasma source according to the first embodiment of the present invention. In FIG. 1, while introducing a predetermined gas from a gas supply device 2 into a vacuum vessel 1, exhausting is performed by a turbo molecular pump 3 as an exhaust device, and the vacuum vessel 1 is kept at a predetermined pressure while being kept at a predetermined pressure. Plasma is generated in the vacuum vessel 1 by supplying a high frequency power having a frequency of 13.56 MHz to the coil 6 on the dielectric plate 5 as a plasma source by the power source 4. A substrate 8 as an object to be processed is placed on the electrode 7. The mask 9 made of aluminum (conductor) is disposed in the vicinity of the substrate 8, and the mask 9 is provided with a minute through hole. A high frequency power of 500 kHz can be supplied to the mask 9 from the high frequency power supply 10 for the mask. A laser displacement meter 11 as a distance measuring device is provided at the end of the mask 9 so that the distance between the substrate 8 and the mask 9 can be measured. Information obtained by the laser displacement meter 11 is fed back to a motor 12 as a distance control device, and the distance between the substrate 8 and the mask 9 is changed to a desired value by changing the position of the mask 9 via the gear box 13. Kept. The sequencer 14 can be programmed to gradually increase or decrease the distance between the mask 9 and the substrate 8.
[0024]
In FIG. 2, the conceptual diagram of the processing method of the to-be-processed object which concerns on 1st Embodiment of this invention is shown. The mask 9 is provided with a large number of minute through holes 15, and an ion sheath is formed on the surface of the mask 9 due to the influence of the high frequency power applied to the mask 9. In the ion sheath, ions 16 which are active particles in the plasma are accelerated in the direction of the mask 9, but the ions 16 leaking through the through holes 14 collide with the substrate 8 with high kinetic energy. By this action, the substrate 8 or a thin film formed on the substrate 8 is etched, and the mask shape is transferred.
[0025]
At this time, when the distance between the mask 9 and the substrate 8 is gradually increased, the region to be etched on the substrate 8 becomes larger due to the spread of the ion flux from the through hole 15 toward the substrate 8. As a result, a forward tapered shape as shown in FIG. 3 can be obtained. It should be noted that the signal line for feedback from the laser displacement meter 11 is shielded so that the motor 12 can be operated without stopping the plasma generated in the vacuum chamber 1.
[0026]
A similar forward tapered shape can be obtained even when the distance between the mask 9 and the substrate 8 is gradually reduced.
[0027]
An example of specific processing conditions is shown below. While supplying 100 sccm of carbon tetrafluoride gas and keeping the pressure in the vacuum vessel 1 at 1 Pa, high frequency power of 1000 W is supplied to the coil 6 to generate plasma in the vacuum vessel 1. Etching the polycrystalline silicon film formed on the substrate 8 while supplying a high frequency power of 200 W to the mask 9 and changing the distance between the mask 9 and the substrate 8 from 50 μm to 350 μm in 3 minutes at a rate of 100 μm / min. Went. At this time, the polycrystalline silicon film was etched by 600 nm, and the cross-sectional shape was a forward tapered shape. The difference between the pattern bottom dimension and the pattern surface dimension was 1.2 μm, and the taper angle was 45 degrees.
[0028]
In the first embodiment of the present invention described above, the case where an inductively coupled plasma source is used to generate plasma in the vacuum vessel is illustrated, but an antenna type plasma source, a microwave plasma source, a parallel plate type Various plasma sources such as a plasma source and an electron cyclotron resonance plasma source can be used.
[0029]
Moreover, although the case where the mask is a conductor and high frequency power is applied to the mask has been illustrated, a negative DC voltage may be applied to the mask. Alternatively, high-frequency power may be applied to a mask coated with an insulator. Alternatively, the same processing can be performed by applying high-frequency power to an electrode on which the workpiece is placed.
[0030]
(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS.
[0031]
FIG. 4 shows a cross-sectional view of a processing apparatus equipped with a microplasma source according to the second embodiment of the present invention. In FIG. 4, a microplasma source 17 is disposed in the vicinity of a substrate 8 as an object to be processed placed on an electrode 18, and a microplasma is generated by applying high frequency power of 100 MHz to the microplasma source 17. To do. The active particles leaking from the microplasma act on the substrate 8 to process the substrate 8. A laser displacement meter 11 as a distance measuring device is provided at the end of the microplasma source 17 so that the distance between the substrate 8 and the microplasma source 17 can be measured. Information obtained by the laser displacement meter 11 is fed back to the motor 12 as a distance control device, and the distance between the substrate 8 and the microplasma source 17 is changed by changing the position of the microplasma source 17 via the gear box 13. It is kept at the desired value. The sequencer 14 incorporates a program so that the distance between the microplasma source 17 and the substrate 8 is gradually increased or gradually decreased.
[0032]
5 is a cross-sectional view of the microplasma source 17 taken along a broken line A in FIG. Two quartz glass plates 19 and 20 are bonded together, and a capillary 21 is formed between them. The reaction gas is introduced into the capillary 21 and ejected as microplasma toward the substrate 8. A high frequency electrode 22 and a ground electrode 23 are provided on both sides of the quartz glass plates 19 and 20, and high frequency power is supplied to the high frequency electrode 22 from a high frequency power supply 24. The microplasma source 17 can operate from 1 Pa to several atmospheres, but typically operates at a pressure in the range from 10 ³ Pa to atmospheric pressure.
[0033]
At this time, when the distance between the microplasma source 17 and the substrate 8 is gradually increased, the area to be etched on the substrate 8 becomes larger due to the spread of the flow of active particles from the microplasma source 17 toward the substrate 8. come. As a result, a forward tapered shape as shown in FIG. 3 can be obtained. It should be noted that the signal line for feedback from the laser displacement meter 11 is shielded so that the motor 12 can be operated without stopping the generated microplasma.
[0034]
A similar forward taper shape can be obtained even when the distance between the microplasma source 17 and the substrate 8 is gradually reduced.
[0035]
An example of specific processing conditions is shown below. Helium gas containing 5% sulfur hexafluoride gas is supplied at 2 slm, high frequency power of 10 W is supplied to the microplasma source 17 under atmospheric pressure, and plasma is generated in the vacuum chamber 1. The silicon substrate 8 was etched while changing the distance between the microplasma source 17 and the substrate 8 from 500 μm to 1000 μm at a rate of 200 μm / min for 2.5 minutes. At this time, the silicon substrate was etched by 5 μm, and the cross-sectional shape was a forward tapered shape. The difference between the pattern bottom dimension and the pattern surface dimension was 10 μm, and the taper angle was 45 degrees.
[0036]
In the second embodiment of the present invention described above, the case where a parallel plate type capillary type is used as the microplasma source has been exemplified. However, other types of capillary types such as an inductively coupled capillary type, a microgap type, an induction type, etc. Various microplasma sources such as a coupled tube type can be used.
[0037]
In addition, by applying high-frequency power to the electrode for placing the object to be processed, it is possible to enhance the action of attracting ions in the microplasma.
[0038]
In the embodiment of the present invention described above, only a part of various variations in the scope of the present invention regarding the shape of the vacuum vessel, the structure and arrangement of the plasma source, and the like are merely illustrated. It goes without saying that various variations other than those exemplified here can be considered in applying the present invention.
[0039]
In addition, although the case where polycrystalline silicon or a silicon substrate is etched is illustrated, the object to be processed is not limited to these, and the present invention can be applied to processing various substrates or coatings coated with various films. Applicable to processing of processed products.
[0040]
Moreover, although the case where carbon tetrafluoride or sulfur hexafluoride gas is used in the etching process is exemplified, the gas is not limited to this, and a mask or a microplasma source is configured according to the material of the object to be processed. It is possible to select a gas that can increase the etching selectivity with the substance to be performed.
[0041]
Moreover, although the case where a laser displacement meter was used as a distance measuring device was illustrated, a contact sensor, a non-contact sensor using atomic force, or the like can also be used. These can be selected depending on the possible cost and the required accuracy.
[0042]
In addition, the case where the etching process is performed while changing the distance between the mask or the microplasma source and the object to be processed is exemplified, but the process of changing the distance while the plasma is stopped and the generation of the plasma while maintaining the certain distance. The processing step may be repeated. Alternatively, the step of changing the distance while the high frequency power or the DC power applied to the electrode on which the mask or substrate is placed is stopped while plasma is continuously generated, and the mask or substrate is placed while maintaining a certain distance. The process of supplying high frequency power or DC power to the electrode to be processed may be repeated.
[0043]
【The invention's effect】
As is apparent from the above description, a vacuum vessel, a gas supply device that supplies gas into the vacuum vessel, an exhaust device that exhausts the inside of the vacuum vessel, and a plasma source that generates plasma in the vacuum vessel; , a high frequency power supply for supplying high frequency power, an electrode disposed in said vacuum container, is between and Rutotomoni penetrations holes are arranged to face the electrode of the electrode and the plasma source is provided to the plasma source a mask which is the distance between the vacuum vessel and the processing object and the mask disposed on the electrode surface provided opposite to the electrode and the distance measuring device for measuring by a laser, the distance measuring device Based on the information obtained, a distance control device that changes the distance between the mask and the object to be processed is provided, so that the patterning shape can be controlled and processing with excellent processing accuracy can be performed. Ukoto can.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a configuration of a processing apparatus according to a first embodiment of the present invention. FIG. 2 is a conceptual diagram of a processing method for an object to be processed according to the first embodiment of the present invention. FIG. 4 is a cross-sectional view showing a configuration of a processing apparatus according to a second embodiment of the present invention. FIG. 5 is a cross-sectional view of a microplasma source according to the second embodiment of the present invention. 6 is a diagram showing the patterning process used in the conventional example. FIG. 7 is a cross-sectional view showing the configuration of the processing apparatus used in the conventional example. FIG. 8 is a cross-sectional view showing the configuration of the processing apparatus used in the conventional example. Explanation】
DESCRIPTION OF SYMBOLS 1 Vacuum container 2 Gas supply apparatus 3 Turbo molecular pump 4 High frequency power supply 5 for coils Dielectric plate 6 Coil 7 Electrode 8 Substrate 9 Mask 10 High frequency power supply 11 for masks 11 Laser displacement meter 12 Motor 13 Gear box 14 Sequencer

Claims (7)

A vacuum vessel, a gas supply device for supplying gas into the vacuum vessel, an exhaust device for exhausting the inside of the vacuum vessel, a plasma source for generating plasma in the vacuum vessel, and supplying high-frequency power to the plasma source to the high-frequency power source, an electrode disposed in said vacuum container, and during and mask opposed disposed Rutotomoni penetrations holes to the electrodes are provided between the electrode and the plasma source, the vacuum container and a distance measuring device for measuring a distance between the object to be processed and the mask disposed on the electrode surface provided opposite to the electrode by a laser, based on the information obtained by the distance measuring device, wherein A processing apparatus comprising: a distance control device that changes a distance between a mask and the workpiece. The processing apparatus according to claim 1, wherein the distance control device is operable without stopping plasma generated in the vacuum vessel. Processing apparatus according to claim 1, wherein the gradually increasing the distance the mask and the object to be processed, or gradually programmable to small. It said mask is a conductor, and the processing apparatus according to claim 1, further comprising a DC power supply for applying a negative DC voltage to the mask. It said mask is a conductor, and the processing apparatus according to claim 1, further comprising a high-frequency power source for applying RF power to the mask. The mask is intended with a coating of insulator to the conductor, and the processing apparatus according to claim 1, further comprising a high-frequency power source for applying RF power to the mask. The processing apparatus according to claim 1, further comprising a high-frequency power source for applying RF power to the electrode for placing an object to be processed.

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