WO1998001898A1

WO1998001898A1 - Rie apparatus

Info

Publication number: WO1998001898A1
Application number: PCT/JP1997/002326
Authority: WO
Inventors: Tadahiro Ohmi; Takahisa Nitta
Original assignee: Kabushiki Kaisha Ultraclean Technology Research Institute
Priority date: 1996-07-04
Filing date: 1997-07-04
Publication date: 1998-01-15

Abstract

A reactive ion etching (RIE) apparatus which has an etching chamber in which O2 and H2O do not exist or into which O2 and H2O are not brought and, further, in which oxygen ions do not exist when a plasma is generated. The etching selection ratio of an object to be treated against resist is determined. A loading chamber (102) into which an object (101) is introduced is connected to the treatment chamber (103) in which the object (102) is etched through a first opening/closing means (104). At least the outermost surfaces of metal contamination preventing means (105) which is provided along the inner walls of the treatment chamber (103), sputtering preventing means (106) which is provided along electrodes in the treatment chamber (103) or/and the inner wall of the treatment chamber (103) are made of material which does not contain oxygen atoms.

Description

Specification

R IE equipment Technical field

The present invention relates to a RIE device. More specifically, the present invention relates to an RIE apparatus having a high etching selectivity of a target object with respect to a resist. Background art

The conventional method of finely processing an object to be processed on a semiconductor substrate is roughly as follows.

■.

First, after applying a resist to the treated body, the treated body is heated. Next, after transferring the pattern onto the object using a stepper or the like, development and heating and drying are performed. Further, the object to be processed is introduced into a reactive ion etching (RIE) apparatus, and a necessary region is etched. However, as the degree of integration of semiconductors increases and, for example, fine processing at a level (design rule: 0.2 to 0.3 m) or less that uses a KrF excimer laser exposure apparatus becomes necessary, Problems are emerging.

In RIE, it is necessary to selectively etch only the area without resist at all, without etching the area with resist. However, the resist and the material of his processed to be etched, for example, selectivity to the S i 0 ₂ and BPSG used as an interlayer insulating film (Borophosphosi l icate Glass) there is a problem that not enough taken.

Conventionally, as a countermeasure for this, there is a method of ensuring a sufficient thickness of the resist. Thus, even if the resist is etched, it is possible to prevent the base material of the resist, that is, the material of the object to be processed from being exposed to plasma and etched.

However, in order to further improve the degree of integration of semiconductors, it is becoming essential to use an excimer laser stepper. Since the depth of focus of the excimer laser stepper is very shallow (0.5-0.7 im), it is necessary to reduce the resist film thickness to about the same thickness. However, when the thickness of the resist is reduced, the selectivity between the resist and the material of the object to be processed (for example, SiO ₂ ) cannot be sufficiently secured as described above. Therefore, it is difficult to introduce an excimer laser stepper. In other words, further fine processing is not possible The problem is becoming apparent.

Incidentally, as it is clear from Atsushingu technique utilizing oxygen plasma, the resist force off: To avoid being etched by plasma is no treatment chamber 0 ₉ or H ₉ 0 to etching processing, or, brought No, if oxygen atoms are not present in the processing chamber when plasma is generated.

Figure 5 shows a schematic diagram of the current RIE equipment. In FIG. 5, reference numeral 501 denotes an object to be processed, 502 denotes a load chamber for introducing the object to be processed 501, 503 denotes a processing chamber for etching the object to be processed 501, and 504 denotes a processing chamber. First opening / closing means, 505: means for preventing metal contamination, 506: means for preventing spatter, 507: lower electrode, 508: upper electrode, 509: matching device, 510: high frequency Power supply, 5 1 1 means for cooling the object 5 1 through the lower electrode 5 0 7, 5 1 2 is an insulator,. 5 1 3 and 5 1 4 are exhaust means, 5 1 5 and 5 1 6 is a gas supply means.

The processing room 503 is made of aluminum base metal, and its inner wall surface is anodized. A1 is around the two electrodes 507 and 508, and the inner wall of the processing chamber 503 is A1. 〇 ₃ ceramic, and, with a shield made of quartz (S i 0 _2)? One has been. A predetermined gas was supplied into the processing chamber 503 by the gas supply means 51δ, and high-frequency electric power of 13.56 μm was introduced to the lower electrode 507 to generate plasma. For example, high-frequency power of 200 W, pressure of 30 mTorr, and C as gas. Loading room 502 is S i ゥ

It was used only for loading and unloading the object 501 to be processed, and was not subjected to any heat treatment. The object 501 before being introduced into the load chamber 502 was transported and stored in a clean room with its surface exposed. The gate valve used as the first opening / closing means 504 was heated from outside by a heating means such as a heater.

However, the current equipment described above (Fig. 5) has the following problems.

(1) Problem of moisture adsorbed on the object to be etched

Even if the object to be processed is sufficiently cleaned, 3 × 10 ¹⁶ molecules / cm of water will be adsorbed on the surface of the object only by exposing the object to air in a clean room. When the target object is considered the case of 2 0 Uweha substrate O mm 0, so that the 1. 9 x 〖0. ^nineteen moisture is incorporated have in the device.

(2) 0 generated from the composition in the interior of the processing chamber ₂ and H ₂ 0 in question

Material to generate a device 0 ₇ and H ₉ 0 also inside is widely used. As those containing H ₉ 0 and 0 ₂ in constructs a device within, for example, to protect the workpiece from metal contamination Because, in order to prevent the packs of a stage that mounts the object, quartz being used (S i 0 ₉₎ or ceramic (A 1.0) it is mentioned for the purpose of. When quartz or ceramic is sputtered by plasma, it emits oxygen atoms (0) as its constituent elements, which adversely affects the selectivity between the resist and the object (eg, SiO 2).

(3) generated from the inner wall of the processing chamber 0 ₂ and H ₂ 0 in question

¾a When an aluminum alloy is used as the material for the inner wall of the treatment room, the surface inside the treatment room is often subjected to alumite treatment. After anodizing, the surface components in the processing chamber become A1θο · nH. When this surface is sputtered by the plasma, (^ and H 0 are released into the processing chamber.

(4) H ₉ 0 and organic problems arising from the resist provided on the target object

Registry itself contains an H ₉ 0 or an organic solvent. The boiling point of the resist dissolved, for example, ethyl resulfate (ECA: Ethlcersolbacetate) is 15; however, the current bakebake after II light and development runs at a lower temperature of 130 ° C. Therefore, H9〇 and organic solvents remain in the resist in large amounts. This residual H ₉ % and organic matter have a significant effect on the etching process.

However, if the temperature is raised to 13 (TC or more and post-baking is performed), the resist becomes glass-shaped, and it is difficult to form an accurate pattern.

(5) The problem of O ₂ H ₉₀ generated from the material of the object to be etched

Material of the workpiece to be etched, for example, when Etsu quenching the S i 0 ₉ film used as an interlayer insulating film, as is clear from the component, 0 ₂ is produced. Since this occurs during the plasma 〇 ₉ can not be effectively evacuated, it is a factor of selection ratio degradation.

(6) in order to remove moisture adsorbed to the inner wall of the 0 ₂ and H ₉ 0 issue processing chamber for generating the closing means provided such between the processing chamber and the load chamber, usually the entire RIE apparatus heating

(Baking). However, for example, for the processing chamber and separated one by which opening and closing means between the load chamber (Kiyoshie If gate valve) can not ίτ Ukoto baking reasons its structure, Eta ₉ 0 generation Was causing it. Also, despite the fact that the temperature of the inner wall of the chamber has risen due to the plasma, the temperature near the gate valve remains at room temperature, so that reaction by-products adhere to the gate valve and cause the generation of particles or the gate valve. Lube was causing a failure.

In the present invention, 0 ₂ or Η ₂₀ does not exist or is brought into a processing chamber for performing an etching process. An object of the present invention is to provide an RIE apparatus in which no oxygen atoms are present in a processing chamber when plasma is generated. Disclosure of the invention

5 The RIE apparatus of the present invention is an RIE apparatus in which a load chamber for introducing an object to be processed and a processing chamber for etching the object to be processed are connected via a first opening / closing means. Metal contamination prevention means provided along an inner wall, spatter prevention means provided along an electrode in the processing chamber, and / or an inner wall of the processing chamber, at least the outermost surface of which does not contain oxygen atoms. It is characterized by.

Ten

Action

Hereinafter, the operation of each claim related to the present invention will be described. .

In the invention according to claim 1, metal contamination prevention means provided along an inner wall of the processing chamber, spatter prevention means provided along an electrode in the processing chamber, and / or an inner wall of the processing chamber have at least: Since the outermost surface is made of a material that does not contain oxygen atoms, metal contamination prevention means, spatter prevention means, and / or plasma generated from the inner wall of the processing chamber into the processing chamber to be etched. 0 to be mixed. However, the amount of 0 can be reduced. As a result, a RIE apparatus having a high selectivity can be obtained.

In the invention according to claim 2, since the material subjected to the fluoridation passivation treatment is used for the inner wall surface of the processing chamber, it is generated from the inner wall of the processing chamber. And H. 0 can be reduced.

In the invention according to claim 3, the pretreatment chamber that performs the UV curing process and the heating process on the resist provided on the object to be processed in a gas atmosphere that does not contain at least oxygen atoms includes the second opening and closing. Since it is in contact with the load chamber through the means, it is possible to reduce O ₂ and H ₂₀ generated from the resist provided on the object to be processed and the material of the object to be etched. . 25 In the invention according to claim 4, since the first or second and the second opening / closing means have a built-in heating mechanism, the amount of reaction by-products generated by the plasma adheres to the opening / closing means. To decrease. As a result, generation of particles can be suppressed, and failure of the opening / closing means can be avoided. In the invention according to claim 5, wherein the load chamber or and the processing chamber, wherein by having a means for heating the object to be processed, before etching the workpiece, from his processed o ₂ and 30 Eta ₉₀ can be removed, and Η ₂₀ adsorbed on the processing body is not brought into the processing chamber. Further, stable etching processing can be performed.

In the invention according to claim 6, since the processing chamber has means for exhausting a reaction by-product gas in a space between at least two electrodes or in the vicinity of the space, plasma generated between the electrodes is provided. The anti-by-product gas can be uniformly removed within the electrode surface. As a result, etching with a small in-plane distribution becomes possible. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a schematic diagram showing an example of a RI device according to the present invention.

FIG. 2 is another example of the R I device related to the present invention, and is a schematic diagram when a pretreatment chamber is provided.

FIG. 3 is a schematic diagram illustrating a state in which the opening / closing means used in the RI device according to the present invention has a built-in heating mechanism.

FIG. 4 is a schematic diagram illustrating a processing chamber provided with a means for exhausting a reaction by-product gas in a space between at least two electrodes or in the vicinity of the space.

FIG. 5 is a schematic diagram showing an example of a conventional RI device.

(Explanation of Shingo)

1 0 1 He processing body,

1 02 Road room,

1 03 Processing room,

1 04 First opening and closing means,

1 05 Metal contamination prevention measures,

1 06 Spatter prevention means,

1 07 Lower electrode,

1 08 Top electrode,

1 09 Matching device,

1 1 0 High frequency power supply,

1 1 1 cooling means,

1 1 2 体

1 1 3, 1 1 4 exhaust means,

1 1 5, 1 1 6 Gas supply means, 2 0 1 Pretreatment chamber,

20 2 Load room,

2 03 Processing room,

20 first opening and closing means,

2 ϋ δ second opening / closing means,

2 06 Gas supply means that does not contain at least oxygen atoms,

2 07 and 2 08 are gas supply means,

2 09, 2 1 0, 2 1 1 Exhaust means,

2 2 1 He body,

2 22 Stage with built-in heating system,

9 one o one,

2 2 4 UV light source,

30 1 Gate valve outer wall,

302 ί

3 03 control rod,

304 0 link ",

305 internal heater,

306 external heater,

4 0 1 Upper electrode,

4 02 Lower electrode,

403 object,

4 04 Gas inlet,

4 05 Gas exhaust,

406 dipole ringmagnet,

40 7 Gas supply means,

408 exhaust means,

4 09 Matching device,

4 1 0 High frequency power supply,

50 1 He processing body,

502 loading room, 503 processing room,

50 first opening and closing means,

505 Metal pollution prevention measures,

506 anti-spatter means,

δ 507 lower electrode,

508 top electrode,

509 matcher,

5 1 0 High frequency power supply,

5 1 1 cooling means,

10 5 1 2 Insulator,

5 1 3, 5 1 4 exhaust means,

5 15 and 5 16 Waste supply means. BEST MODE FOR CARRYING OUT THE INVENTION

15 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

The RI device according to the present invention has a configuration as shown in FIGS. 1 and 2, for example.

In FIG. 1, reference numeral 101 denotes a processing object, reference numeral 102 denotes a load chamber for introducing the processing object 101, reference numeral 103 denotes a processing chamber for etching the processing object 101, and reference numeral 104 denotes a first opening / closing unit. Means, 105 is metal contamination prevention means, 106 is spatter prevention means, 107 is lower electrode, 108 is upper electrode 20 poles, 109 is matching box, 110 is high frequency power supply, 1 1 1 is lower Means for cooling the object to be processed 101 through the electrode 106, 112 is an insulator, 113, 114 are exhaust means, and 115, 116 are gas supply means.

The apparatus shown in FIG. 2 differs from the apparatus shown in FIG. 1 in that an object to be processed 221 is introduced into a load chamber 202 via a pretreatment chamber 201.

25 Processing room 102 is a chamber made of AI alloy or SUS.

The metal contamination prevention means 105 provided along the inner wall of the processing chamber 102, the spatter prevention means 106 or Z provided along the electrodes in the processing chamber, and the inner wall of the processing chamber 102 are at least the outermost surface. Was formed of a material not containing an oxygen atom, for example, carbide, nitride, or fluoride.

That is, the metal contamination prevention means 105, the spatter prevention means 106, and / or the inner wall of the processing chamber 30102 may be made of carbide, nitride, or fluoride itself. Suitable charcoal Examples of the material and nitride include SiC, A1N, SiN, and the like.

In order to increase the selectivity between the resist (not shown) provided on the object 101 and the material of the object 101 to be etched (for example, SiO 2), We have taken various measures.

5 From the outside of the RIE equipment into the processing chamber 102. Because and H ₂ 0 is to prevent brought, subjected to means of the following two.

To prevent H ₂ 0 and 0 ₉ remaining in the various gases used in Γ process', aimed at purity of various gases to be used (impurity concentration 5 ppb or less). In addition, there is no external leakage, no organic matter is used inside, and the gas contact part is Cr. 0 ₃ using a gas system of performing a passivation process. 0 By this measure, we will be able to obtain ₂₀ or 0 from the measures I 15 and 1 16. Supply will disappear.

: Two methods are implemented to avoid being adsorbed and brought into the object to be processed. The first method is to not expose the object to the clean room. By storing and transporting the treated material in a gas that does not contain oxygen atoms (gas with a residual moisture of 5 ppb or less), for example, N ₉ , Ar, dry air, and transports the treated material, This method does not adsorb moisture. Specifically, a chan- nel having a transport mechanism for transporting a processing object filled with a gas containing at least elemental atoms between the RI III apparatus and the processing apparatus before bringing the processing object into the RI II apparatus. Can be directly connected, or a closed box filled with a gas with low residual moisture can be used.

20 The second method is to expose the workpiece to the air in the clean room. When introducing the workpiece into the equipment, it has a heating mechanism and a loading chamber or heating that can introduce a gas with low residual moisture. The object to be treated is introduced into the chamber, the temperature is raised to about 2 δ0 ° C in the chamber, and the water adsorbed on the front and back surfaces of the object is batch-purged using a gas with low residual moisture. This is the method of removing.

25 Therefore, by storing and transporting the object in a gas that does not contain oxygen atoms at least without exposing the object in a clean room, moisture will not be adsorbed on the front and back surfaces of the object. The water adsorbed on the RIE equipment will not be brought into the RIE equipment. Even if the object is exposed in the clean room, the water adsorbed on the object can be removed in the loading chamber and heating champer, so 30 minutes of water adsorbed on the object waits in the RIE equipment. Never be. In order to prevent H ₂ 〇 and O ₂ inside the RIE equipment, that is, inside the processing chamber 103, from being brought into the plasma, the constituent materials of the equipment, the object to be processed, and the object to be processed The following three measures were applied to the above registry.

The metal contamination preventing means 105 provided along the inner wall of the processing chamber 103, the spatter preventing means 106 provided along the electrode in the processing chamber, and / or the inner wall of the processing chamber 103 are at least The surface was formed of a material that does not contain oxygen atoms, such as carbide, nitride, and fluoride. That is, the metal contamination preventing means 105, the spatter preventing means 106, or the inner wall of the processing chamber 103 may be itself a carbide, a nitride, or a fluoride. Moreover, metal contamination prevention means 1 0 5, sputtering evening prevention means 1 0 6, or and the inner wall of the processing chamber 1 0 3, and per se e.g. A ₇ 0 ₃ and S i 0. Even if the outermost surface is a material that does not contain oxygen atoms, it is good to use suitable carbides, nitrides, and fluorides as S i C, A 1. \\ S i · \, A 1 _{F Q Z .Vl g FX i F} 2, F e F 2 and the like.

(4) As the constituent material of the chamber itself used as the processing chamber 103, alumite-treated A1 base metal was not used, and a material subjected to fluoridation passivation treatment was used. A 1 F ₃ ZM g F ₂ , i F when the chamber material itself is A 1 base metal. Etc., when the material of the chamber itself is S Ji S using materials that do not contain F e F _2, etc., an oxygen atom (0).

^ In a gas atmosphere containing at least no oxygen atoms, a pretreatment chamber 201 for performing λ-curing treatment and heat treatment on a resist provided on the object to be treated is provided with a second opening / closing means 20. 4 and connected to the load chamber 202. After subjecting the object to be treated to UV curing in an atmosphere containing at least oxygen atoms, the object to be treated with a registry in a gas atmosphere containing at least no oxygen atoms is subjected to UV curing. 5 0. A high temperature bake of C was performed. By intends catty this series of processing, since the water or organic solvent in without resist the register Bok is deformed is completely removed, without 〇 ₂ or an organic solvent is released into the chamber, the precise Etching becomes edible.

By etching the Si ₀₉ , 0 was generated inside the processing chamber 103. The following measures were taken to effectively and quickly remove reaction products such as.

First, it is necessary to make the process space as narrow as possible. For this reason, a parallel plate type plasma device is used to make the gap between both electrodes as small as possible, and to reduce the ion energy applied to the substrate. A D RiM (Dipole Ring Magnet) system with a horizontal magnetic field was adopted. Second, by providing an exhaust port in the upper electrode and exhausting air therefrom, reaction by-products can be more effectively removed.

Thirdly, a pump with a large flow rate and a large displacement, for example, a mechanical booster pump or a rotary pump with a capacity of 51 Zin to 101 Zm 1 n will be adopted. Further by增加the raw material gas flow rate Te 5 to adjust the A r gas flow rate, a decrease in the relative amount of reaction products 0 ₀ like generated from the S i 0 _o.

With these three measures, the reaction product can be quickly exhausted, and the reaction product does not adversely affect the etching.

The gate valve used as the opening / closing means 104, 204, 205 usually heats only from the outside of the valve 10. At the same time, the mixture is heated to 80 ° C. or higher, preferably 130 ° C. or higher, to prevent moisture adsorption and suppress reaction product adsorption. Therefore, by heating the inside of the gate valve and heating to the valve valve seat, not only the water adsorbed on the valve can be removed, but also the reaction product does not adhere, and the selectivity can be improved. Rather, it contributes to improving the operation rate of equipment. Example

Hereinafter, the RIE apparatus of the present invention will be described with reference to the drawings, but the present invention is not limited to these examples.

20 (Example 1)

In this example, using the RIE apparatus shown in FIG. 1, by changing the material of the processing chamber 1 0 3 internal structure was observed the generation of H ₂ 0 and 0 ₂ in the processing chamber 1 0 3. This observation was performed by connecting a quadrupole mass spectrometer (QM S) having a differential exhaust system (not shown) to the processing chamber 103.

25 as an object to be processed 1 0 1, using those provided S I_〇 ₂ film and the resist on the S i wafer by a predetermined etching process, the selection ratio (S i 0 ₉ film etching rate / Registering speed). Further, a gate valve was used as the first opening / closing means shown in FIG.

As the resist, THMR-iP330, manufactured by Tokyo Ohka Kogyo Co., Ltd. was used. Etching gas 30 scan uses a CF ₄ / H?, Such that the etch rate of the S I_〇 ₂ film is about 5 0 nm / min, moth Pressure, gas flow rate, and high frequency power applied to the electrodes were appropriately controlled.

As for the structure inside the processing room 103, metal contamination prevention means 105, spatter prevention means 106, and the inner wall of the processing room 103 were examined, and the four combinations shown in Table 1 were considered. The amount of H-W and ₀₉ generated in was examined.

Condition Α is a combination corresponding to the conventional technology. Processing chamber 1 0 3 Arumai bets treated consist A 1 alloy chamber having an inner wall, among which A 1 ₂ 〇 _third metal pollution hand stage 1 0 5 and sputter prevention means S i 0 106 was provided.

Condition B differs from condition A only in that the inner wall of the processing chamber 103 is SiC.

The condition C differs from the condition A only in that the anti-sparging means 106 is set to S i C.

Condition D is different from condition A in that the metal contamination prevention means 105, the spatter prevention means 106, and the inner wall of the processing chamber 103 are all SiC.

(table } )

Table 2, in each condition, H ₂ 0 and 0. Is the result of the generation amount and the selection ratio. The results of conditions B to D are normalized by the values obtained in condition A. H ₂ 0 and 0 ₂ of the generation amount was determined from the respective molecular weight of 8 and 3 2 results. H in condition A. 0 0 ₂ generation amount were respectively a ^{4 X 1 0- 10 A, 2} 1 0- 10 A in ion current value. : Table 2)

ιυ

From Table 2, the metal contamination prevention means provided along the inner wall of the processing chamber, the shatter prevention means provided for the electrode in the processing chamber, or the inner wall of the processing chamber are at least the outermost surface.

Fifteen

By There was a material containing no oxygen atom, metal contamination prevention means, sputtering means for preventing, or Roh and, from the inner wall of the processing chamber, Ya 0 ₉ to be mixed into the plasma that is occurring in the processing chamber for etching process it was found that it is possible to reduce the amount of Eta ₉ 0. As a result, an RI III device having an excellent selectivity was obtained.

(Example 2)

20

In this example, the processing method dependence of the inner wall of the processing chamber 103 was examined. Two methods were used to treat the inner wall: condition D: alumite treatment and condition ：: fluoridation passivation (A 1 F ₃ / Mg F ₂ ).

The metal contamination preventing means 105 and the spatter preventing means 106 were both SiC. Other points were the same as in Example 1.

twenty five

Table 3, in each condition, the results of H © 0 0 ₂ generation amount and selectivity. The results of Condition E are shown normalized by the values obtained under Condition D.

30 (Table 3

From Table 3, full 'to the inner wall surface of the ½ sense chamber; for a material in which the / passivated treatment was found to be reduced 0 0 ₉ Ya 1 Ri generated from the inner wall of the processing chamber. As a result, it was confirmed that the selectivity also improved.

(Example 3)

In this example, by changing the heat treatment method of Regis Bok, was examined generation amount and selectivity of H ₂ 0 and 0 ₉ in the processing chamber 1 0 3.

At that time, in a gas atmosphere containing at least no oxygen atoms, a pretreatment chamber for performing a V cure treatment and a heat treatment on the resist provided on the treatment body is prepared. The RIE device (Fig. 2) was used to connect the RIE device with the second opening / closing means.

In FIG. 2, reference numeral 201 denotes a pre-processing chamber, reference numeral 202 denotes a load chamber, reference numeral 203 denotes a processing chamber, reference numeral 205 denotes first opening / closing means, reference numeral 204 denotes second opening / closing means, and reference numeral 206 denotes At least oxygen gas-free gas supply means, 207 and 208 are gas supply means, 209 to 211 are exhaust means, 221 is an object to be processed, and 222 is a built-in heating system. The stage, 2 2 3 is a window, and 2 2 4 is a UV light source.

The metal contamination preventing means and the spatter preventing means of the processing chamber 203 were both SiC. Further, the processing chamber 2 0 3, the processing method of the load chamber 2 0 2 and pretreatment chamber 2 0 1 inner wall, fluoride passivated - was _{(A 1 F ./ g F 2} ) treatment. Gate valves were used as the first and second opening / closing means 205 and 204.

The following three combinations were examined for the heat treatment method for the resist.

Condition F is a combination corresponding to the prior art. That is, after the resist was provided on the Si wafer, no heat treatment was performed. The object to be processed 221 was merely passed through the pretreatment chamber 201 under atmospheric pressure. Condition G is as follows: In the pretreatment chamber 201 under atmospheric pressure, a resist was set up on Si ゥヱ ha. Was. Condition H is different from condition G in that baking is performed at 230 ° C.

In Condition I, the same heat treatment as in Condition H was performed while flowing dry air as a gas containing at least no oxygen atom into a pretreatment chamber under atmospheric pressure.

Conditions J, the vacuum (if ί Retsue 1 0- ² Τοι table) points with pre-treatment chamber under the Ru different from the conditions I. The same heat treatment as in H was performed.

V-curing means that UV light [wavelength 220 to 270 nm, 8 mW / c (250 nm)] is applied to the object 2 21 from the UV light source 2 24 Means irradiation for 15 minutes through 23. In addition, baking means to apply heat to the processing body 21 for 15 minutes using a heater built in the stage 222.

The other points were the same as in Example 1.

Table 4, in each condition, the result of H ₂ 0 and 0 ₂ generation amount and selectivity. The results for Conditions G to J are normalized by the values obtained under Condition F.

(Table 4)

From Table 4, it was subjected to heat treatment in the pretreatment chamber 2 0 1, 0 generation amount of ₂ or H ₂ 0 is reduced, it was found that improved selectivity. In addition, at least oxygen ■ It was also confirmed that the introduction of a gas that does not contain offspring further enhances the effect. It turned out that, under the conditions H and I, there was almost no change in the resist shape even after the heat treatment, and there was little degassing from the resist after the heat treatment. Furthermore, as a result of the condition J, it was found that a series of processing was performed under intimidation and the effect was highest.

Also, it was found that even when the pretreatment chamber was used as an independent box without using the second opening / closing means, the selectivity was improved as compared with the condition Η.

In addition, even in the case of condition F (without ripening treatment), by introducing a gas containing at least no oxygen atom, the amount of generated 0 ₂ and Η ₂₀ is reduced compared to condition F, and the selectivity is improved. For the trend / two.

(Example 4)

In this example, a method of heating the first opening / closing means 104 in the RI device of FIG. 1 was studied. As the first opening / closing means 1 () 4, the gate valve shown in FIG. 3 was used. In FIG. 3, reference numeral 310 denotes an outer wall of a gate valve, reference numeral 302 denotes a gate valve, reference numeral 303 denotes a control rod of a gate valve 302, reference numeral 304 denotes a ring, and reference numeral 304 denotes a gate valve. Reference numeral 303 denotes an internal heater installed on the outer wall of the gate valve.

In the load chamber 102 and the processing chamber 103, no heat treatment was performed.

(4) Both the metal contamination prevention means 105 and the spatter prevention means 106 of the processing room I 03 were S i. The processing method of the inner wall of the processing chamber 1 0 3 and the load chamber 1 0 2 were fluoride passivated _{_{t A 1 F 9 g F 9}} ) process.

The following three combinations were considered.

Condition K is a combination corresponding to the conventional technology. In other words, the internal heater 300 and the external heater 310 of the first opening / closing means are all at 0 fί, and no heating is performed at all.

The condition L differs from the condition のみ only in that the external heater 303 of the first opening / closing means is baked or always ο η. The setting during baking was 130 ° C, and the setting during etching was 80 ° C.

The condition M is different from the condition K in that the internal heater 300 of the first opening / closing means is set to on only during baking. The setting during baking was 130 ° C.

The condition N differs from the condition K in that the internal heater 300 of the first opening / closing means is always on. The setting during baking was 130 ° C, and the setting during etching was 80 ° C. This was the same as in Example 1.

Table 5 shows the amounts of H ₉ 〇 and ₀₉ generated and the selection ratio under each condition. The results under the conditions L to N are normalized by the values obtained under the condition K.

(Table 5)

Table 5, the first switching means 1 0 4, the amount of 0 ₂ and Eta ₂ 0 be heated from the outside is not reduced. It was found that the generation of O ₂ and Η ₂₀ was reduced and the selectivity was improved by applying heat from the inside. In addition, when the first opening / closing means 104 is heated from the inside, the effect is further enhanced by always on (that is, heating is continued not only during the baking but also during the etching process). Was also confirmed.

In addition, when the first opening / closing means 104 is constantly heated, the reaction products generated by the etching process do not adsorb to the first opening / closing means〗 04, so that the amount of particles generated in the processing chamber is reduced. There was also an action to do. As a result, the advantage that the frequency of occurrence of a failure in the first switching means 104 was reduced was also confirmed.

It goes without saying that the above-mentioned effects can be obtained to some extent even with the opening / closing means of (2).

(Example 5)

In this example, the heat treatment of the object to be processed in the load chamber 102 in the RIE apparatus of FIG. 1 was studied. A lamp heater (not shown) was used as a means for heating the object in the load chamber. In the first opening / closing means 104 and the processing chamber 103, no heat treatment was performed. ¾The metal contamination prevention means 105 and the spatter prevention means 106 of the processing room I 03 were both SiC. The processing method for the inner walls of the processing chamber 103 and the load chamber 102 was fluoridation passivation IA 1 F ₃ / Mg F) processing.

The following three combinations were considered.

Condition (2) is a combination corresponding to the prior art. That is, this is the case where the object to be processed is not heated at all in the load chamber 102. Specifically, an object to be processed is introduced into the load chamber 102, the pressure in the load chamber 102 is reduced to a level of 10 to ⁸ Torr, and then the object to be processed is placed in the depressurized ¾α processing room. Was moved.

The condition ρ is determined by using a lamp heater (not shown) provided in the code chamber 102.

It differs from the condition ◦ in that it is heated for 150 minutes and 15 minutes.

Condition Q differs from condition が in that the treated body is heated for 250 minutes by a lamp heater (not shown) provided in the load chamber 102 for 15 minutes.

The other points were the same as in Example 1.

Table 6 under the conditions, the result of Eta ₀ 〇 0 ₂ generation amount and selectivity. The results under conditions P and Q are normalized by the values obtained under condition 0.

(Table 6)

From Table 6, it was found that the selectivity was improved by heating the object in the load chamber 102. In addition, when treated at a high temperature of about 250 ° C, a remarkable effect was confirmed. Further, it goes without saying that the above-mentioned effects can be obtained to some extent even in the pretreatment chamber 201 in the case of using the RIE apparatus of FIG. (Example 6)

In this cooling, the processing chamber 103 of the RIE apparatus shown in Fig. 1 was constructed using the DRM (Dipole Ring Magnet) system shown in Fig. 4. The processing chamber shown in FIG. 4 differs from Example 1 in that a means for exhausting a reaction by-product gas is provided in or near the space between at least two electrode poles.

In FIG. 4, reference numeral 401 denotes an upper electrode, reference numeral 402 denotes a lower electrode, reference numeral 403 denotes a processing body, reference numeral 404 denotes a gas-filled vent, reference numeral 405 denotes a gas exhaust port, and reference numeral 406 denotes a die ball. A ring magnet, 407 is a gas supply means, 408 is an exhaust means, 409 is a matching device, and 410 is a high frequency power supply.

'' The following four points were adopted as means for exhausting by-product gas.

I The distance d between the upper electrode 401 and the lower electrode 402 was kept at 30 mm or less.

2: The upper electrode 410 was provided with gas exhausting mechanisms 404 and 405.

A dipole ring and magnet 406 were provided on the outer periphery of the processing chamber.

) As the gas exhaust means 408 in the processing chamber, a pump capable of exhausting a large flow rate (for example, 500 liters) was used.

Other points were the same as the condition D of the first embodiment.

As a result, when such a means for exhausting the reaction by-product gas is used, the object to be processed during the etching process is less likely to be exposed to the reaction by-product gas, so that the selectivity is further improved. I found out. Industrial applicability

As described above, according to the present invention, it is possible to obtain an RIE apparatus in which (^ or H ₂₀ does not exist or is not brought into a processing chamber for performing an etching process. The selectivity is improved, and it is possible to provide an RIE apparatus that can sufficiently adapt to fine processing with a design rule of 0.2 to 0.3 m or less.

Claims

RIE (reactive 'ion' etching ') wherein a load chamber for introducing a $$ processing object and a processing chamber for etching the object to be processed are connected via first opening and closing means. Device 5

Metal contamination prevention means provided along the inner wall of the processing chamber, sock prevention means provided along an electrode in the processing chamber, and / or the inner wall of the processing chamber, at least the outermost surface does not contain oxygen atoms. RIE equipment characterized by being a material.

2. The RIE apparatus according to claim 1, wherein an inner wall surface of the processing chamber is made of a material subjected to a fluoridation passivation treatment.

3. In a gas atmosphere containing at least no oxygen atoms, a pretreatment chamber for subjecting the resist provided on the object to be processed to a V cure treatment and a heat treatment is provided through a second opening / closing means. 3. The RIE device according to claim 1, wherein the RIE device is surrounded by a storage chamber.

4. The RIE apparatus according to claim 1, wherein the first and / or second opening / closing means has a built-in heating mechanism.

5. The RIE apparatus according to claim 1, wherein the load chamber or Z and the processing chamber have means for heating the object to be processed.

6. The processing chamber according to any one of claims 1 to 5, wherein the processing chamber has a means for exhausting reaction by-product power in a space between at least two electrodes or in the vicinity of the space. The RI II device described in ①.

0