JP3175276B2 - Reaction processing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reaction processing apparatus for forming a resist pattern by dry development in a process of manufacturing a semiconductor device such as an IC or LSI.

[0002]

2. Description of the Related Art Conventionally, in the process of manufacturing semiconductor devices such as ICs and LSIs, a negative type photoresist in which bisazide is mixed with a polyisoprene cyclized product or a quinonediazide compound is mixed in a novolak resin on a substrate to be processed. G photoresist (wavelength 436 nm) and i-ray (wavelength 36 nm) of a mercury lamp through a pattern mask.
(5 nm), and a photolithography method of forming a resist pattern by developing with a developer.

However, in recent years, semiconductor devices have been further miniaturized, and the minimum size of a resist pattern to be formed on a substrate is less than 1 μm, and moreover, is entering a region around 0.5 μm. In such a dimension region, even if a conventional photolithography method using a developing solution for development is used, particularly when a substrate having a step structure is used, the influence of light reflection at the time of exposure and the exposure system Due to a problem such as a small depth of focus, a problem arises in that a sufficient resolution of the resist pattern cannot be obtained.

[0004] In order to solve such a problem, hexamethyldisilazane (hereinafter referred to as HMDS) is used in a step before applying the radiation-sensitive resin in order to improve the adhesion between the substrate and the radiation-sensitive resin. In order to subject a substrate to a surface treatment with a reactive compound containing silicon such as silicon, a reaction processing apparatus has been proposed in which the reactive compound is introduced into the substrate from a single port or hole.

In JP-A-61-107346, a photoresist containing a photoactive compound and a polymer is exposed to i-line or g-line of a mercury lamp or far-ultraviolet light through a pattern mask, and the exposed portion is, for example, HMDS or the like. A dry development process in which the silicon compound is selectively acted on to perform silylation, and then the unsilylated portion is etched by using a reactive ion etching apparatus that generates oxygen plasma to thereby develop a resist pattern. Used in the step of silylation in
A plurality of holes for guiding the reactive silicon compound onto the substrate, and an upper heating plate and a lower heating plate which are located above and below the substrate and maintain the temperature of the substrate at a high temperature, a sealable reaction provided inside. A reaction processing device having a vessel is disclosed.

[0006] Instead of a silicon compound, a treatment with a germanium compound is performed to selectively perform gel milling.

[0007]

However, in the above prior art, the reactive compound could not be uniformly guided on the substrate and could not be brought into uniform contact with the substrate, resulting in uneven processing of the substrate and poor productivity.

The present invention solves the conventional problems and provides a reaction processing apparatus capable of performing uniform reaction processing over the entire surface of a substrate and thereby performing fine pattern processing with high accuracy while maintaining high productivity. The purpose is to do.

[0009]

In order to achieve the above-mentioned object, after subjecting a substrate on which a radiation-sensitive resin layer according to the present invention is formed to a radiation treatment, and before a dry development treatment, a silicon compound or a germanium compound is used. In a reaction processing apparatus for performing a process with a reactive compound, a reactor having a reactive compound inlet and capable of reducing pressure, a substrate provided in the reactor, the substrate is placed, and the temperature of the substrate is controlled. A structure that is provided between the reactive compound introduction port and the temperature controllable plate, and guides the reactive compound onto the substrate placed on the temperature controllable plate. And a plate-shaped member having a portion for shielding the reactive compound from being directly introduced into the substrate.

It is desirable that the configuration of the plate member is as follows. That is, on a straight line connecting the center of the substrate and the center of the reactive compound introduction port in the reaction processor, a plate that does not allow the passage of the reactive compound, preferably a thin disk, has a minimum diameter larger than the maximum diameter of the substrate. With respect to the uniform mesh-shaped plate, the reactive compound introduction port side or the substrate side, preferably the reactive compound introduction port side, is brought into close contact with the mesh-shaped plate, and the center is on the straight line. To be located at The solid angle Ω _{1 of the} plate that does not allow passage of the reactive compound viewed from an arbitrary point on the circumference of the reactive compound inlet at that time is Ω ₁ > 0.42 × 2π sr (steradian), and the reactivity is It is desirable that the solid angle at the bottom of the reaction chamber as seen from an arbitrary point on the circumference of the compound introduction port be Ω ₂ or less.

In the present invention, the plate-like member (hereinafter, referred to as a "blocking plate") provided between the substrate and the reactive compound introduction port as described above, and the substrate are placed and the temperature of the substrate is reduced. Materials for forming the temperature-controllable plate to be controlled include, for example, aluminum and stainless steel, but are not particularly limited as long as they are not affected by the reactive compound.

In controlling the temperature of the substrate, a plurality of temperature controllable plates, for example, an upper temperature controllable plate can be used in addition to the above-mentioned temperature controllable plate for mounting the substrate.

When the reactive compound is introduced into the reactor, it is usually introduced in a gaseous state. In this case, the reactive compound gas is introduced together with an inert carrier gas such as nitrogen or helium. Alternatively, it can be directly introduced as a liquid, for example, in the form of a mist, into a evacuated reactor, and gasified in the reactor. The reactive compound is supplied in a gaseous state to a reactor (about 600
The flow rate of the gas when introduced into cc) is usually 0.01 to 1
0 l / min, preferably 0.1 l / min to 3.5 l
/ Min, and the time for contacting the reactive gas with the substrate is usually 5 seconds to 7 minutes, preferably 10 seconds to 5 minutes.
Further, the total pressure in the reactor is typically 50-900 mmH
g, preferably 100 to 760 mmHg.

The substrate to which the above-described processing in the apparatus of the present invention is applied is a semiconductor substrate such as silicon or gallium-arsenic, a glass substrate, a diamond substrate, or a silicon or gallium-arsenic having a radiation-sensitive resin layer. Semiconductor substrate, glass substrate, diamond substrate and the like. Here, examples of the radiation-sensitive resin include a radiation-sensitive resin composed of an alkali-soluble resin such as a novolak resin or polyhydroxystyrene and a quinonediazide compound or a bisazide compound.Examples of the reactive compound to be brought into contact with the resin layer include: , HMDS and tetramethyldisilazane, and germanium compounds such as bis- (trimethylgermyl) amine and bis- (dimethylgermyl) amine. In addition, as the reactive compound for processing when the substrate is processed for the purpose of increasing the adhesion between the substrate and the radiation-sensitive resin applied to the substrate, a silicon compound such as HMDS can be used.

[0015]

According to the present invention, a plate-shaped member having a central portion for shielding the reactive compound and a peripheral portion for allowing the reactive compound to pass therethrough is provided between the reactive compound introduction port and the substrate to thereby increase the reactivity. Since the treatment with the compound can be performed uniformly over the entire surface of the substrate, fine pattern processing can be performed with high accuracy while maintaining high productivity by combining with the dry development treatment.

[0016]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows an embodiment of the reaction processing apparatus according to the present invention, which is used in a silylation step of a photolithography method disclosed in Japanese Patent Application Laid-Open No. 61-107346.

Here, reference numerals 1A and 1B denote an upper member and a lower member of the reactor 1 which are separable up and down, respectively. Can be kept. Here, the upper member is fixed here, but the lower member may be fixed.

Reference numeral 2 denotes an upper temperature controllable plate, 3 denotes a lower temperature controllable plate having a built-in heater, and 4 denotes a plate provided on the side of the reactor lower member 1B and is connected to the lower temperature controllable plate 3. A temperature-controllable seal member, which can keep the space between the upper temperature-controllable plate 2 and the upper temperature-controllable plate 2 airtight when the reactor 1 is closed by the upper member 1A. The upper temperature controllable plate is not necessarily required to be temperature controllable, and may be anything or may not be provided as long as the temperature distribution in the reactor is not significantly uneven.

5 is mounted on the lower temperature controllable plate 3,
It is a substrate that undergoes a reaction process at a controlled temperature, and can be fixed to the lower temperature-controllable plate 3 by vacuum chucking with a vacuum pump 6. However, the substrate 5 does not have to be fixed to the lower temperature controllable plate 3 in close contact with the lower temperature controllable plate 3, and may be floated and held from the lower temperature controllable plate 3 by a plurality of pins.

The substrate 5 has a radiation-sensitive resin layer that has been subjected to a radiation irradiation treatment. When the reactor 1 is kept in a sealed state, an appropriate space is provided between the substrate 5 and the upper temperature controllable plate 2. Make sure that a proper gap is maintained. Here, the controlled temperature may be a constant temperature throughout the reaction process or may be changed.

The upper temperature controllable plate 2 must be provided with a reactive compound inlet 7 for introducing a reactive compound into the reaction chamber. The upper temperature controllable plate 2 has a blocking plate 8 in a gap between the upper temperature controllable plate 2 and the substrate 5. The blocking plate 8 will be described later in detail.

The reactive compound 10 composed of a silicon compound stored in the bubbler 9 is uniformly guided to the substrate 5 from the above-described reactive compound inlet through a blocking plate as required. The bubbler 9 is provided with a circulating water supply system, and the temperature of the bubbler 9 can be controlled by the circulating water to adjust the temperature of the silicon compound. Thereby, the concentration of the reactive compound sent together with the inert carrier gas into the reactor 1 can be adjusted, and at the same time, the supply amount of the reactive compound can be appropriately controlled by a flow control device such as a mass flow controller (not shown). Can be. Reference numeral 11 denotes a heating device for avoiding condensation of the reactive compound.

During the reaction or before and after the reaction, the pressure in the reactor can be maintained at an appropriate level by the vacuum pump 12. The treatments before and after the reaction referred to herein include, for example, heating, cooling, or blowing the reactor with an inert gas to replace the atmosphere. Reference numeral 13 denotes a condenser, and reference numeral 14 denotes a reactive gas trap. Reactive compounds and gases ordered during the process can be guided to the trap 14 by the pump 12 after being cooled by the condenser 13 as necessary. It is.

FIG. 2 shows an example of the blocking plate. The blocking plate includes a central plate 8A through which the reactive compound does not pass, and a mesh-like portion 8B through which the reactive compound passes. The mesh-shaped portion 8B for guiding the reactive compound of the blocking plate to the substrate has a path size of 1 to 200 μm, passes through the center of the blocking plate, and is uniform with the center axis perpendicular to the blocking plate as the center of symmetry. Is desirable.
FIG. 3 shows another example of the blocking plate. FIG.
(A) is a plate 8C that does not allow a reactive compound to pass through, a thin annular portion 8D, a central disk portion 8E, and an arm 8F connecting both of them.
It consists of FIG. 3B shows a uniform mesh plate 8G. As shown in the side view of FIG.
And tightly integrated. At this time, it is more desirable that the plate 8C is on the side of the reactive compound introduction port.

The uniform mesh portion 8B or the mesh plate 8G may be a plate having a plurality of holes. However, in this case, it is desirable to change either the number density of the holes or the diameter of the holes or their product in proportion to the distance from the center of the blocking plate.

In the reaction processing apparatus configured as described above, the substrate 5 after forming the latent image of the circuit pattern by the radiation irradiation processing is mounted on the lower temperature controllable plate 3 of the reactor 1 and The reactor 1 is closed by raising the member 1B. In this case, the upper temperature controllable plate 2 and the lower temperature controllable plate 3 are 50 ° C. to 250 ° C.
Further, the periphery of the substrate 5 is kept airtight between the sealing member 4 and the upper temperature controllable plate 2.

Then, the pressure around the substrate 5 is reduced to a degree of vacuum of about 10 to 500 mmHg by the vacuum pump 12, and then the reactive compound gas is supplied from the bubbler 9 using nitrogen as an inert carrier gas to the upper temperature-controllable plate 2. Is uniformly released onto the substrate 5 from the reactive compound inlet 7 through the blocking plate 8. At this time, the supply amount of the reactive compound gas is controlled by the above-described method. Thus, the substrate 5 is placed in the reactive compound gas atmosphere for usually 5 seconds to 7 minutes, preferably 10 seconds to 5 minutes. Leave for a minute.

In this case, the reactive compound gas may be constantly or intermittently flowed around the substrate 5. Then, at the stage when the reaction is completed, the reactive compound gas is led to the condenser 13 by the pump 12,
To be collected.

Although the temperature controllable plates 2 and 3 are arranged in the reactor 1 in this embodiment, the temperature is controlled before the substrate 5 is brought into the reactor 1 in order to further increase the productivity. As described above, a means for controlling the temperature in a reduced pressure or normal pressure atmosphere may be provided.

Example 1 On a 6-inch silicon wafer, a partial ester compound of 6-diazo-5,6-dihydro-5-oxo-1-naphthalenesulfonic acid chloride and a novolak resin and 6-diazo-5,6 A mixture of -dihydro-5-oxo-1-naphthalenesulfonic acid, dissolved in propylene glycol monomethyl acetate, was applied by spin coating to a thickness of 1.5 µm, and an i-line having an aperture coefficient of 0.50 was applied. Using a stepper, a uniform line and space pattern was exposed over the entire surface of the wafer.

Next, the configuration of the blocking plate provided between the reactive compound introduction port and the substrate is a uniform mesh-like radius of 85 m made of SUS316 as shown in FIG.
A thin plate as shown in FIG. 3A having a structure of holding a 25 mm-radius disk at the center of a 5 mm-wide thin ring from 8 directions with a 2 mm arm on a thin flat disk of SUS316 As shown in FIG. 3 (C), the reactor was brought into close contact with the compound introduction port to form an integral unit. The reactor was fitted with a stainless steel upper temperature controllable plate and a stainless steel lower temperature controllable plate. The exposed silicon wafer was housed. After baking at 160 ° C. for 3 minutes before treatment at a pressure of 150 mmHg, HMDS (bubbler temperature of 50 ° C., N ₂ flow rate of 1.0 l / min) was fed into the reactor (60).
0 cc), and subjected to a silylation treatment at 160 ° C. for 4 minutes at a total pressure of 760 mmHg, HMDS concentration of 0.5% by volume.

At this time, the distances between the reactive compound inlet and the blocking plate and between the blocking plate and the substrate were 10 mm, respectively, and the solid angles Ω ₁ and Ω ₂ of the disk having a radius of 25 mm and the bottom of the reactor were determined by the reactivity. Ω ₁ = 3.95 steradians and Ω ₂ = 5.24 steradians, respectively, as viewed from any point on the periphery of the compound introduction port.

The wafer was subjected to a power of 1 kW and a gas flow rate of 7 using a magnetron reactive ion etching apparatus Aries-C manufactured by Materials Research Corporation.
When oxygen etching was performed at 0 SCCM and a pressure of 4 mTorr, line-and-space patterns of 0.4 to 1.0 μm were formed at regular intervals according to the design dimensions. Further, the line width of 71 points was measured for the 0.6 μm equally-spaced line and space pattern over the entire surface of the wafer at a magnification of 30,000 times by the attached length measuring mechanism on the screen of the scanning electron microscope. When the ratio of the standard deviation of the population to the average value was determined as a reliable index of the uniformity of the line width, a value indicating a high uniformity of 1.4% was obtained.

Example 2 The radius of the disk 8E in the center of the plate 8C of the blocking plate was changed to 8 mm, 16 mm and 35 mm, and the pattern size uniformity on the substrate (standard deviation 3σ) was changed in the same manner as in Example 1. I asked. FIG. 4 shows the results. If the radius of the disk is 16 mm or less and exceeds 35 mm, the uniformity deteriorates, and high uniformity is obtained in the middle. A radius of 16 mm of the disk corresponds to a solid angle of 0.42 steradians of the disk viewed from any point on the circumference of the reactive compound inlet, and a radius of 35 mm is also from any point on the circumference of the reactive compound inlet. Equal to the solid angle of the substrate seen.

Comparative Example 1 In Example 1, the reactive compound was introduced directly into the substrate from the reactive compound introduction port without providing an on-plate member between the reactive compound introduction port and the substrate.

The ratio of the standard deviation to the average value of the 0.6 μm equally-spaced line-and-space pattern was calculated in the same manner as in Example 1. As a result, a value of 5.0% was obtained.

COMPARATIVE EXAMPLE 2 In Example 1, the plate member provided between the reactive compound inlet and the substrate was a SUS316 uniform mesh-shaped thin disk, and the reactive compound was directly introduced into the substrate. 0.6μ
The ratio of the standard deviation to the average value of the m equally-spaced line-and-space pattern was 2.5%.

In the case of this comparative example, the reactive compound inlet was
Since the pattern size is right above the center of the substrate to be processed, the pattern size at the center of the substrate is extremely thin compared to the pattern size of other portions. This is because, for example, a reactive compound having a different temperature (for example, 50 ° C.) is introduced into the substrate to be processed on the temperature controllable plate whose temperature is controlled to 160 ° C., so that the temperature unevenness on the substrate to be processed is caused. And it is considered that this leads to uneven processing. That is, even if the reactive compound is uniformly distributed on the substrate, the flow of the reactive compound on the substrate causes the temperature distribution to be non-uniform on the substrate to be processed due to the flow, resulting in an uneven reaction. On the other hand, the blocking plate according to the present invention has a function of reducing the flow of the reactive compound on the substrate, which causes the temperature non-uniformity on the substrate, whereby the uniform processing on the substrate is achieved. Is performed.

[0040]

As described above, according to the present invention,
The substrate on which the radiation-sensitive resin layer that has been irradiated
A uniform mesh-shaped part that guides the reactive compound to the substrate by placing it on a lower temperature controllable plate kept at a constant temperature in a closed reactor and an inlet for the reactive compound to the substrate By supplying the reactive compound onto the substrate via a plate-shaped member consisting of a part that shields from being directly guided from the substrate, processing with the reactive compound composed of a silicon compound can be performed uniformly over the entire surface of the substrate Therefore, in combination with the dry development processing, fine pattern processing of 0.4 μm to 1.0 μm can be performed with high accuracy while maintaining high productivity.

Similarly, in the treatment with a germanium compound, high productivity can be obtained by increasing the uniformity of the treatment.

In addition, even in the processing for improving the adhesion between the substrate and the radiation-sensitive resin, the processing unevenness is reduced, so that the productivity can be remarkably improved.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing one embodiment of a reaction processing apparatus of the present invention.

FIG. 2 is a top view illustrating an example of a blocking plate.

FIGS. 3 (A), (B) and (C) are a top view and a side view showing an example of a case where a blocking plate is constituted by two plates.

FIG. 4 is a characteristic diagram showing a relationship between a disc radius of a blocking plate and a standard deviation of a pattern dimension.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Reactor 1A Upper member 1B Lower member 2 Upper temperature controllable plate 3 Lower temperature controllable plate 4 Sealing member 5 Substrate 6 Decompression pump 7 Reactive compound inlet 8 Blocking plate 9 Bubbler 10 Reactive compound 11 Heating device 12 Decompression Pump 13 condenser 14 trap

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Kenji Yanagihara 2--11-24 Tsukiji, Chuo-ku, Tokyo Japan Synthetic Rubber Co., Ltd. (56) References JP-A-4-236425 (JP, A) JP-A Heisei 4-287047 (JP, A) JP-A-3-95559 (JP, A) JP-A-2-151865 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01L 21/027

Claims (2)

(57) [Claims] 1. A reaction processing apparatus for performing a treatment with a reactive compound comprising a silicon compound or a germanium compound after subjecting a substrate on which a radiation-sensitive resin layer is formed to radiation treatment and before performing dry development treatment, A reactor having a reactive compound inlet, capable of being depressurized, a temperature controllable plate provided in the reactor for mounting the substrate and controlling the temperature of the substrate, and the reactive compound inlet And a portion having a structure provided between the substrate and the temperature controllable plate, the structure having a structure for guiding the reactive compound onto the substrate placed on the temperature controllable plate, and the reactive compound is directly applied to the substrate. And a plate-like member having a portion for shielding so as not to be introduced into the reaction device. 2. A solid angle Ω of a site for shielding the reactive compound viewed from an arbitrary point on the periphery of the reactive compound introduction port.
₁ is Ω ₁ > 0.42 × 2π sr, and is not more than a solid angle Ω ₂ of the bottom surface of the reaction chamber as viewed from an arbitrary point on the circumference of the reactive compound introduction port. Item 1
The reaction processing apparatus according to item 1.