JP2005294541A - Treatment device and treatment method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a treatment device easily capable of processing the front surface of a matter to be treated within a short period of time utilizing proximity field light. <P>SOLUTION: The treatment device for treating the front surface of a silicon oxide film 52 equipped with a pattern 57 made of a metal on the front surface thereof is provided with a vacuum chamber 1 for receiving the silicon oxide film 52, a gas introducing port 3 for introducing gas into the vacuum chamber 1, a plasma treatment device 11 provided in the vacuum chamber 1 to treat the front surface of the silicon oxide film 52 employing the gas introduced from the gas introducing port 3, and a lamp 10 for treating the silicon oxide film 52 by optical processing by irradiating light to the silicon oxide film 52 to generate near-field light on the bottom 58 of the pattern 57 and to treat the silicon oxide film 52 by optical treatment. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a processing apparatus and a processing method for processing the surface of a workpiece.

  Photolithography using near-field light is known (for example, see Patent Document 1). In this photolithography, the metal mask pattern formed on the surface of the glass substrate and the object to be treated are brought into close contact with each other, and light is irradiated from the back side of the glass substrate, so that the opening of the mask pattern. The object to be processed is exposed by oozing near-field light.

A plasma processing method using near-field light is also known. In this plasma processing method, the surface of an object to be processed is optically processed with near-field light, and the processing efficiency of plasma processing performed thereafter is improved.
JP 2001-15427 A

  However, in the plasma processing method using near-field light in combination, a so-called near-field probe that generates near-field light is used, so that there is a problem that the processing area is small and processing takes time.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a processing apparatus and a processing method capable of processing the surface of an object to be processed in a short time and easily using near-field light.

  In order to solve the above problems and achieve the object, the processing apparatus and the processing method of the present invention are configured as follows.

(1) In a processing apparatus for processing the surface of an object to be processed having a metal pattern on the surface, a chamber for storing the object to be processed, a gas inlet for introducing gas into the chamber,
A processing means that is provided in the chamber and that processes the surface of the object to be processed using a gas introduced from the gas inlet, and irradiates light toward the object to be processed, so that the pattern bottom of the pattern is irradiated. Irradiation means for generating near-field light and optically processing the object to be processed is provided.

(2) The processing apparatus according to (1), wherein the processing means converts the gas into plasma to process the surface of the object to be processed.

(3) The first step of treating the surface of the workpiece having a metal pattern on the surface, and irradiating light toward the workpiece before the first step, A second step of generating near-field light on the pattern bottom of the pattern to light-treat the surface of the object to be processed.

(4) In the processing method described in (3), the surface of the object to be processed is processed with plasma in the first step.

(5) A first step of treating the surface of the workpiece having a metal pattern on the surface with plasma, and irradiating light toward the workpiece during the first step. And a second step of generating near-field light on the pattern bottom of the pattern and activating the plasma.

(6) The processing method described in (3) or (4), wherein in the first step, a film formation process or an etching process is performed on the surface of the object to be processed.

  ADVANTAGE OF THE INVENTION According to this invention, the surface of a to-be-processed object can be processed easily for a short time using near field light.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  First, the first embodiment of the present invention will be described with reference to FIGS.

  Initially, the structure of the process board | substrate which is a process target which concerns on this Embodiment is demonstrated.

  FIG. 2 is a configuration diagram of the processing substrate according to the first embodiment of the present invention.

  As shown in FIG. 2A, the processing substrate 50 has a silicon substrate 51. The silicon substrate 51 has a diameter of about 200 [mm], and a silicon oxide film 52 is formed on the surface thereof to a thickness of about 500 [nm].

  On the surface of the silicon oxide film 52, the first titanium-based thin film 53, the metal film 54, and the second titanium-based thin film 55 have thicknesses of about 20 [nm], about 300 [nm], and about 60 [nm], respectively. Are formed sequentially.

  The first titanium-based thin film 53, the metal film 54, and the second titanium-based thin film 55 are patterned in a predetermined shape in the previous process. As a result, on the surface of the silicon oxide film 52, a pattern 57 made of the first titanium-based thin film 53, the metal film 54, and the second titanium-based thin film 55 and having both a line width and a groove width of about 120 [nm]. Is formed.

  The organic film 56 formed on the second titanium-based thin film 55 is a resist mask pattern used when the first titanium-based thin film 53, the metal film 54, and the second titanium-based thin film 55 are patterned. Is the rest. The first and second titanium-based thin films 53 are made of titanium and titanium nitride, and the metal film 54 is made of aluminum, silicon, and copper.

  Next, the plasma processing apparatus according to the first embodiment of the present invention will be described.

  FIG. 1 is a schematic view of a plasma processing apparatus according to a first embodiment of the present invention.

  As shown in FIG. 1, the plasma processing apparatus has a vacuum chamber 1. An opening 1a is provided in the upper wall of the vacuum chamber 1, and a dielectric window 2 made of quartz glass is provided in the opening 1a.

  A gas introduction port 3 for introducing a source gas and an etching gas is formed on the side wall of the vacuum chamber 1, and an exhaust port 4 for exhausting the source gas and generated gas remaining in the vacuum chamber 1 on the lower wall. Is formed.

  Inside the vacuum chamber 1 is provided a stage 5 for placing a processing substrate 50 to be processed. A high frequency power source 6 provided outside the vacuum chamber 1 is connected to the stage 5. The high frequency power source 6 applies a high frequency bias current (for example, 13.56 MHz) to the stage 5.

  A heater (not shown) for heating the processing substrate 50 placed on the stage 5 is embedded in the stage 5.

  A coil device 7 is provided on the upper surface side of the dielectric window 2. An RF power source 8 is connected to the coil device 7. The RF power source 8 causes a high-frequency current (for example, 2 MHz) to flow through the coil device 7 to generate high electron density plasma in a plasma generation chamber 9 provided on the lower surface of the dielectric window 2. That is, the high frequency power source 6, the coil device 7, the RF power source 8, and the plasma generation chamber 9 constitute a plasma processing apparatus 11 that performs plasma processing on the processing substrate 50.

  A plurality of lamps 10 are provided above the coil device 7 so as to face the dielectric window 2. Each of these lamps is composed of a light source 10a and a reflective cover 10b, and irradiates the processing substrate 50 on the stage 5 through the dielectric window 2 with uniform intensity as indicated by arrows.

  In this embodiment, an excimer laser oscillator (wavelength: 308 nm) is used as the light source 10a. However, the present invention is not limited to this, and may be appropriately selected according to processing conditions. Further, in the present embodiment, the lamp 10 is arranged outside the vacuum chamber 1, but it may be provided inside the vacuum chamber 1.

  Next, the operation when using the plasma processing apparatus having the above configuration will be described.

  When the processing substrate 50 is placed on the stage 5, the inside of the vacuum chamber 1 is almost in a vacuum state, and light is irradiated from the lamp 10. When the processing substrate 50 is irradiated with light, part of the light enters the metal film 54 and near-field light is generated at the pattern bottom 58. This near-field light breaks the interatomic bond on the outermost surface of the silicon oxide film 52 and generates dangling bonds 52a on the outermost surface of the silicon oxide film 52 as shown in FIG.

  In the present embodiment, the groove width of the pattern 57 is about 120 [nm], and the wavelength of the light (excimer laser) emitted from the lamp 10 is about 308 [nm]. For this reason, the propagation light from the lamp 10 does not reach the pattern bottom 58.

  When a predetermined time elapses after the processing substrate 50 is irradiated with light, the lamp 10 is turned off, and an interlayer insulating film 59 (see FIG. 2C) is formed on the surface of the processing substrate 50 by plasma CVD.

  The processing conditions are substrate temperature: 350 [° C.], source gas: SiH 4 / O 2 / Ar gas, bias power: 1300 [W], and ICP power 5000 [W].

  At this time, since the dangling bond 52a is generated on the surface of the silicon oxide film 52 by the irradiation of near-field light, the probability of attachment of ions or radicals in the plasma to the silicon oxide film 52 is improved.

  As a result, the deposition rate in the thickness direction of the interlayer insulating film 59 is increased near the pattern bottom 58 and the coverage is improved, so that the size and number of voids generated in the interlayer insulating film 59 can be reduced. it can.

  According to the plasma processing apparatus having the above-described configuration, before the interlayer insulating film 59 is formed on the surface of the silicon oxide film 52 by plasma CVD, near-field light is generated on the pattern bottom 58 to thereby generate the surface of the silicon oxide film 52. A dangling bond 52a is generated in the substrate.

  Therefore, the probability of adhesion of ions and radicals to the silicon oxide film 52 is improved, so that the deposition rate in the thickness direction of the interlayer insulating film 59 is increased. Thereby, the coverage is improved, and the size and number of voids generated in the interlayer insulating film 59 can be reduced. As a result, an interlayer insulating film 59 having a good film quality is formed on the surface of the silicon oxide film 52, and leakage between wirings and a decrease in reliability are suppressed.

  On the other hand, the inventors have confirmed that many large voids are generated in the interlayer insulating film 59 when the interlayer insulating film 59 is formed on the processing substrate 50 without using near-field light. This result indicates that the interlayer insulating film 59 having a good film quality is formed on the surface of the silicon oxide film 52 by the action of the near-field light.

  In addition, since the near-field light can be generated on the pattern bottom 58 simply by irradiating light from the lamp 10 toward the processing substrate 50, the surface of the processing substrate 50 is excellent in a short time and easily. It is possible to form an interlayer insulating film 59 having a proper film quality.

  In the present embodiment, near-field light is used to generate dangling bonds on the surface of the silicon oxide film 52, but the present invention is not limited to this. For example, normal propagation light may be used. Good. However, when propagating light is used, it is necessary to make the wavelength shorter than the groove width of the pattern 57.

  However, it is difficult to introduce short-wavelength light into a plasma processing apparatus because the space occupied by the generation source is large, the cost is high, and the light is absorbed by air or glass. Furthermore, recently, semiconductor elements have been manufactured with a rule of 100 [nm]. When light in the vacuum ultraviolet region that can be used for this fine pattern is used, the material of the dielectric window 2 is extremely limited. End up.

  However, if near-field light is used as in the present embodiment, the above-described problem does not exist, so that dangling bonds can be generated on the surface of the silicon oxide film 52 easily and at low cost.

  In this embodiment, the interlayer insulating film 59 is formed on the surface of the processing substrate 50 by plasma CVD after irradiating light from the lamp 10. Alternatively, the interlayer insulating film 59 may be formed on the surface of the processing substrate 50 by plasma CVD.

  As a result, ions, neutral molecules, and radicals in the plasma existing near the pattern bottom 58 are activated by the energy of near-field light, and ions and radicals deposited and deposited on the silicon oxide film 52 increase. The inventors have confirmed that there are almost no voids in the interlayer insulating film 59 formed by plasma processing of the processing substrate 50 during irradiation of light from the lamp 10.

  Next, a second embodiment of the present invention will be described with reference to FIG. In addition, the description is abbreviate | omitted here about the structure and effect | action similar to the said embodiment.

  Initially, the structure of the process board | substrate 60 which is a process target which concerns on this Embodiment is demonstrated.

  FIG. 3 is a configuration diagram of a processing substrate according to the second embodiment of the present invention.

  As shown in FIG. 3A, the processing substrate 60 has a silicon substrate 61. The silicon substrate 61 has a diameter of about 200 [mm], and a gate oxide film 62 and a polysilicon film 63 are sequentially formed on the surface with thicknesses of about 3 [nm] and about 60 [nm], respectively. Yes.

  A metal film 64 and a silicon nitride film 65 are sequentially formed on the surface of the polysilicon film 63 with thicknesses of about 50 [nm] and about 100 [nm], respectively. These metal film 64 and silicon nitride film 65 are patterned into a predetermined shape in the previous step.

  As a result, a pattern 66 made of the metal film 64 and the silicon nitride film 65 and having a line width and a groove width of about 80 [nm] is formed on the surface of the polysilicon film 63. The metal film 64 is made of tungsten.

  Next, the operation when using the plasma processing apparatus having the above configuration will be described.

  When the processing substrate 60 is placed on the stage 5, the polysilicon film 63 is etched by plasma etching as shown in FIG. 3B by irradiating light from the lamp 10 and using the pattern 66 as a mask.

  The processing conditions are substrate temperature: 50 [° C.], etching gas: HBr / Cl 2 / O 2 gas, pressure: 6 [mT], bias power: 50 [W], and ICP power 600 [W].

  When the processing substrate 60 is irradiated with light, part of the light enters the metal film 64 and near-field light is generated at the pattern bottom 67. This near-field light excites the etching gas existing near the pattern bottom 67 and increases ions and radicals. Thereby, the etching of the polysilicon film 63 is promoted, and the etching rate is improved.

  According to the plasma processing apparatus configured as described above, near-field light is generated at the pattern bottom 67 when the polysilicon film 63 is etched.

  Therefore, the etching gas existing near the pattern bottom 67 is excited by the near-field light and ions and radicals near the surface of the polysilicon film 63 are increased, so that the etching rate of the polysilicon film 63 is improved. Thereby, even if the aspect ratio of the pattern 66 becomes high, the polysilicon film 63 can be etched at a high etching rate.

  The inventors actually etched the polysilicon film 63 using a pattern with a groove width of about 100 [nm], and measured the etching rates when the present invention was applied and when the present invention was not applied.

  As a result, the etching rate when the present invention is applied is only 10% lower than the isolated pattern, whereas the etching rate when the present invention is not applied is decreased by 20% relative to the isolated pattern. Was confirmed.

  As a result, if the polysilicon film 63 is etched by applying the present invention, even if etching is performed using a pattern having a region having a different groove width, the etching layer is affected by the difference in the groove width. Since it is not so much, damage to the gate oxide film 62 caused by over-etching can be prevented.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Further, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine suitably the component covering different embodiment.

  Specifically, in the above embodiment, the present invention is applied to the formation of the interlayer insulating film 59 on the silicon oxide film 52 and the etching of the polysilicon film 63. However, the present invention is not limited to these. It can be applied to various processes.

  In the above embodiment, the present invention is applied to a semiconductor device manufacturing process. However, the present invention is not limited to this. For example, a high-density hard disk drive (HDD), an optical photonics crystal, plasma, etc. The same effect can be obtained even if it is applied to any process for processing a fine pattern using.

  Furthermore, although the present invention is applied to plasma processing in the above embodiment, it is not necessary to be limited to this.

1 is a schematic view of a plasma processing apparatus according to a first embodiment of the present invention. The block diagram of the process board | substrate which concerns on the 1st Embodiment of this invention. The block diagram of the process board | substrate which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Vacuum chamber, 3 ... Gas introduction port, 10 ... Lamp, 11 ... Plasma processing apparatus, 57 ... Pattern, 52 ... Silicon oxide film, 63 ... Polysilicon film, 58, 67 ... Pattern bottom.

Claims (6)

In the processing apparatus for processing the surface of the workpiece having a metal pattern on the surface,
A chamber for containing the workpiece;
A gas inlet for introducing gas into the chamber;
A processing means provided in the chamber and processing the surface of the object to be processed using a gas introduced from the gas inlet;
Irradiation means for irradiating light toward the object to be processed, generating near-field light at the pattern bottom of the pattern, and light-treating the object to be processed;
A processing apparatus comprising:   The processing apparatus according to claim 1, wherein the processing means converts the gas into plasma to process the surface of the object to be processed. A first step of treating the surface of the workpiece having a metal pattern on the surface;
Before the first step, by irradiating light toward the object to be processed, thereby generating near-field light on the pattern bottom of the pattern and performing a light treatment on the surface of the object to be processed; ,
The processing method characterized by comprising.   The processing method according to claim 3, wherein in the first step, the surface of the object to be processed is processed with plasma. A first step of treating the surface of the workpiece having a metal pattern on the surface with plasma;
A second step of activating the plasma by generating near-field light at the pattern bottom of the pattern by irradiating light toward the object to be processed during the first step;
The processing method characterized by comprising.   6. The processing method according to claim 3, wherein in the first step, a film forming process or an etching process is performed on the surface of the object to be processed.

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