JPH1060655A - Formation of thin film and apparatus therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for forming thin films which have a high density and good coverage, is resistant to cracking and has improved moisture resistance by controlling the hydrogen content in the thin films and an apparatus therefor. SOLUTION: This apparatus has a film forming chamber 101 including a holder for holding a coated substrate 102 and an electrode 105 placed with a target for sputtering, a means 109 for impressing DC or high-frequency electric power to this electrode, means 106, 107 for supplying gases to this film forming chamber, a means 104 for discharging the gases from the film forming chamber and a means for supplying microwave electric power to the film forming chamber via an endless annular waveguide 11. The gases are introduced into the film forming chamber and plasma is formed by the microwave electric power introduced therein via the endless annular waveguide and is impressed on the target electrode 105 for sputtering. The thin films are formed on the coated substrate by controlling the content of the hydrogen taken into the thin film.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for forming a thin film on a coated substrate by introducing a gas into a film forming chamber, applying the gas to a target electrode for sputtering, and generating a plasma.

[0002]

2. Description of the Related Art A film is formed on a substrate by a DC sputtering method, which is an example of a method of forming a thin film, as follows.
Here, the configuration of the DC sputtering apparatus will be described. FIG. 3 is a sectional view of the DC sputtering apparatus. Reference numeral 301 denotes a film forming chamber;
2 is a base, 303 is a support of the base 302, 304 is an exhaust pipe, 305 is a target electrode, 306 is a magnet for generating a magnetron magnetic field, 307 is a gas introduction pipe, and 308 is a DC power supply. The pressure in the film forming chamber 301 is reduced to a value of 10 ⁻⁶ Torr via an exhaust system (not shown). Next, a gas is introduced into the film formation chamber 301 from the gas introduction pipe 307, and the pressure in the film formation chamber 301 is maintained at a desired pressure. Furthermore, DC power supply 30
From 8, a voltage is applied to the target electrode 305 to generate plasma, and a deposited film is formed on the surface of the base 302.

A film is formed on a substrate by a microwave CVD method, for example, as follows. Where microwave CV
3 shows a configuration of the D apparatus. FIG. 4 is a sectional view of the microwave CVD apparatus. Reference numeral 401 denotes a film formation chamber, 402 denotes a substrate,
03 is a support of the base 402, 404 is an exhaust pipe, 405 is a first gas introduction pipe, 406 is a second gas introduction pipe, 407
Is a dielectric, and 408 is a waveguide. The pressure in the film forming chamber 401 is reduced to a value of 10 ⁻⁶ Torr via an exhaust system (not shown). Next, a gas is introduced into the film formation chamber 401 from the gas introduction pipes 405 and 406, and the pressure in the film formation chamber 401 is maintained at a desired pressure. Further, the microwave is applied from the waveguide 408 to the dielectric 4.
The plasma is introduced into the film formation chamber 401 through the layer 07 to generate plasma, and a deposited film is formed on the surface of the base 402.

[0004]

However, in the sputtering method in the above-mentioned conventional example, the density of the formed film may be high even at a low temperature, but the coverage is not so good, and the film may be brittle and cracks may occur. In addition, the proportion of dangling bonds terminated with hydrogen is small, and moisture resistance may be a problem. On the other hand, the CVD method has good coverage, the film is flexible and hardly cracks, and is terminated with hydrogen, so there are few dangling bonds and excellent moisture resistance. There is a problem. As described above, the conventional one has a problem in that both the high density and the good coverage and the difficulty of cracking are satisfied.

Accordingly, the present invention solves the above-mentioned problems of the prior art, and controls the hydrogen content in the thin film, thereby achieving high density, good coverage, low cracking, and low moisture resistance. It is an object of the present invention to provide an improved thin film forming method and apparatus.

[0006]

According to the present invention, there is provided a film forming chamber including a holder for holding a coated substrate, an electrode on which a sputtering target is mounted, and a direct current or a direct current applied to the electrode. Means for applying high-frequency power, means for supplying gas to the film formation chamber, means for exhausting from the film formation chamber, and means for supplying microwave power to the film formation chamber via an endless annular waveguide A gas is introduced into the film forming chamber, plasma is generated by microwave power introduced through the endless annular waveguide, and a plasma is applied to a target electrode for sputtering. Forming a thin film on the coated substrate by controlling the hydrogen content. And in the thin film forming method of the present invention,
The content of hydrogen incorporated in the thin film can be controlled by changing the gas flow rate / sputtering power. Further, in the present invention, the waveguide can be constituted by an endless annular waveguide with a slot. In the present invention, the means for supplying the gas includes a step of introducing a first gas mainly contributing to sputtering from the vicinity of the target, and a step of independently forming a film by plasma without reacting with sputtered particles. It is possible to adopt a configuration including a step of introducing a second gas not to be introduced from the vicinity of the endless annular waveguide and a step of introducing a third gas for forming a film by plasma alone from the vicinity of the base. In this case, it is preferable that Ar is used as the first gas, N2 or O2 is used as the second gas, and SiH4 or organoaluminum is used as the third gas. In the present invention, it is preferable to use Si or Al as the target.

[0007]

DETAILED DESCRIPTION OF THE INVENTION As described above, the present invention generates plasma by microwave power introduced through an endless annular waveguide and applies it to a target electrode for sputtering, thereby incorporating the plasma into the thin film. The hydrogen content is controlled to form a thin film on the coated substrate.
That is, a parallel plate sputtering apparatus is combined with a microwave CVD apparatus that supplies microwave power to an endless annular waveguide, and the hydrogen content is controlled by making the sputtering method and the CVD method compatible, so that the coverage is good and the crack And a thin film having a high density is formed with improved moisture resistance.

Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a sectional view of a thin film forming apparatus used in the thin film forming method of the present invention. 101 is a film forming chamber, 102 is a coating substrate, 103 is a support of the coating substrate 102, 104 is an exhaust pipe, 105 is a target electrode, 106 is a first gas introduction pipe, 107 is a second gas introduction pipe, and 108 is A third gas introduction tube, 109 is a DC power supply, 110 is a dielectric, and 111 is a waveguide.

The configuration of gas introduction is composed of three parts: a first gas introduction pipe 106, a second gas introduction pipe 107, and a third gas introduction pipe 108. From the first gas introduction pipe 106, a gas (sputtering gas) mainly contributing to sputtering is introduced from near the target. Second gas introduction pipe 107
From endless annular waveguide, a gas (reactive gas) that reacts with particles sputtered from the target when performing reactive sputtering and a gas that does not form a film by plasma alone when performing CVD (plasma generating gas). Introduced along the tube. In addition, a dielectric is used as the material of the introduction tube so as not to affect the introduction of microwaves. Third
A gas for forming a film by plasma alone (film forming gas) is introduced from the vicinity of the base 102 from the gas introduction tube 108.

The pressure in the film forming chamber 101 is reduced to a value of 10 ^-6 Torr via an exhaust system (not shown). Next, a gas is introduced into the film formation chamber 101 from the gas introduction pipes 106, 107, and 108, and the pressure in the film formation chamber 101 is maintained at a desired pressure. Next, a microwave is introduced into the film forming chamber 101 from the waveguide 111 via the dielectric 110 to generate plasma. Further, a voltage is applied from the DC power supply 109 to the target electrode 105,
A film is formed on the surface of the base 102. By appropriately selecting a gas and a target to be used by using the thin film forming method of the present invention, it is possible to form a silicon nitride film, a silicon oxide film, an aluminum oxide film, and other various kinds of deposited films.

Now, the hydrogen content and the flow rate of SiH4 /
FIG. 5 shows the relationship between the sputtering voltages. The vertical axis indicates the hydrogen content (unit: cm ^-3 ), and the horizontal axis indicates the ratio of SiH4 flow rate to sputtering voltage (unit: sccm / V). Was expressed. In either case, the hydrogen content tends to increase as the ratio of SiH4 flow rate / sputtering voltage increases. The hydrogen content is generally lower when the film formation temperature is 300 ° C. than when it is room temperature.

The gases introduced through the sputter gas (gas mainly contributing to the sputter) introduction pipe include H 2, H
e, Ne, Ar and the like. When forming a Si compound based thin film such as silicon nitride or silicon oxide, N2, O2,
H2 and the like.

The substrate formed by using the thin film forming apparatus of the present invention may be conductive, electrically insulating, or semiconductor.

[0014]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. Embodiment 1 In Embodiment 1 of the present invention, the thin film forming method of the present invention is applied to the formation of a silicon nitride film for a magneto-optical disk. This embodiment will be described with reference to FIG. FIG. 2 is a sectional view of the thin film forming apparatus. As the base 102,
A polycarbonate (PC) substrate [φ3.5 inches, heat-resistant temperature of 60 ° C.] was used, and Si was used as the target electrode 105. First, the base 102 is used as a support 103 for the substrate.
And the pressure in the film forming chamber 101 was reduced to a value of 10 ⁻⁶ Torr via an exhaust system (not shown). Ar is supplied from the first gas introduction pipe 106 at a flow rate of 200 sccm to the film forming chamber 1.
01, and N2 is introduced into the second gas introduction pipe 107 through the second gas introduction pipe 107.
The gas is introduced into the film formation chamber 101 at a flow rate of 0 sccm, SiH4 is introduced into the film formation chamber 101 from the third gas introduction pipe 108 at a flow rate of 50 sccm, and the pressure in the film formation chamber 101 is set at 5 mTo.
The pressure was maintained at rr. Next, 3 kW power oscillated from a 2.45 GHz microwave power supply (not shown) was introduced into the film forming chamber 101 from the slotted annular waveguide 111 via the dielectric 110 to generate plasma. DC power supply 1
From 09, a voltage of 250 V was applied to the target electrode 105 to start film formation, and a film was formed on the surface of the base 102.
1. A hydrogen density of 1.5 × 10 ²¹ cm ⁻³ or less, no cracks, good coverage, and a film density with improved moisture resistance.
A dense film of 8 g / cc was formed.

Embodiment 2 In Embodiment 2 of the present invention, the thin film forming method of the present invention is applied to the formation of a silicon oxide film on a liquid crystal display substrate. This embodiment is also described with reference to FIG. As the base 102, an electrode (such as an ITO film or A
1) was used, and Si was used as the target electrode 105. First, the base 10
2 was placed on a substrate support 103, and the pressure in the film forming chamber 101 was reduced to a value of 10 ⁻⁶ Torr via an exhaust system (not shown). 200 sc of Ar from the first gas introduction pipe 106
cm2 is introduced into the film forming chamber 101 at a flow rate of 20 cm, and O2 is supplied from the second gas introduction pipe 107 at a flow rate of 20 sccm.
And SiH4 is introduced from the third gas introduction pipe 108 to 1
The film was introduced into the deposition chamber 101 at a flow rate of 00 sccm,
01 was maintained at a pressure of 5 mTorr. next,
A 3 kW power oscillated from a 2.45 GHz microwave power supply (not shown) was introduced from the annular waveguide with slots 111 through the dielectric 110 into the film forming chamber 101 to generate plasma. Further, the DC power supply 109 supplies the target electrode 105
To the substrate 102 by applying a voltage of 100 V
A film was formed on the surface of. Hydrogen content is 7.5 × 10 ²¹ c
At m ^-3 , a dense film with no cracks, good coverage, and improved moisture resistance and a film density of 3.0 g / cc was formed.

Embodiment 3 In Embodiment 3 of the present invention, the thin film forming method of the present invention is applied to the formation of an aluminum oxide film on a liquid crystal display substrate. This embodiment will be described with reference to FIG. FIG. 1 is a sectional view of a thin film forming apparatus. 212 is a means for supplying high-frequency power to the support. Plastic was used for the base 202, and Al was used for the target electrode 205. First, the base 102 was placed on the substrate support 203, and the pressure in the film forming chamber 201 was reduced to 10 ^-6 Torr via an exhaust system (not shown). Ar was introduced into the film formation chamber 201 from the first gas introduction pipe 206 at a flow rate of 180 sccm, and O 2 was introduced from the second gas introduction pipe 207.
Is introduced into the film forming chamber 201 at a flow rate of 30 sccm,
TMAl (trimethylaluminum) was introduced into the deposition chamber 201 at a flow rate of 50 sccm from the gas introduction pipe 208 of
The pressure in the film forming chamber 201 was maintained at a pressure of 5 mTorr. Next, a microwave power supply of 2.45 GHz (not shown)
3kW power oscillated from the annular waveguide 21 with slots
1 was introduced into the film forming chamber 201 through the dielectric 210 to generate plasma. At the same time, a high frequency was applied to the support 203 of the base 202 from the RF power source 212. DC power supply 2
From 09, a voltage of 125 V was applied to the target electrode 205 to start film formation and form a film on the surface of the base 202.
The hydrogen content is 3.0 × 10 ²¹ cm ⁻³ , there is no crack, the coverage is good, and the film density with improved moisture resistance is 4.0.
A dense film of g / cc was formed.

[0017]

According to the present invention, as described above, the plasma is generated by the microwave power introduced through the endless annular waveguide, and the plasma is applied to the target electrode for sputtering. Since the thin film is formed on the coated substrate by controlling the content, it is possible to achieve both the sputtering method and the CVD method, thereby controlling the hydrogen content in the film, thereby improving the coverage. And a thin film having high film density with improved crack resistance and improved moisture resistance can be formed.

[Brief description of the drawings]

FIG. 1 is a sectional view of a thin film forming apparatus according to Embodiments 1 and 2 of the present invention.

FIG. 2 is a sectional view of a thin film forming apparatus according to a third embodiment of the present invention.

FIG. 3 is a sectional view of a thin film forming apparatus according to a conventional example.

FIG. 4 is a sectional view of a thin film forming apparatus according to a conventional example.

FIG. 5 is a graph showing the relationship between the hydrogen content and the flow rate of SiH4 / sputtering voltage.

[Explanation of symbols]

 101: film forming chamber 102: substrate 103: substrate support 104: exhaust pipe 105: target electrode 106: first gas introduction pipe 107: second gas introduction pipe 108: third gas introduction pipe 109: DC power supply 110: Dielectric 111: Waveguide 201: Deposition chamber 202: Substrate 203: Substrate support 204: Exhaust pipe 205: Target electrode 206: First gas introduction pipe 207: Second gas introduction pipe 208: Second 3 gas introduction pipes 209: DC power supply 210: Dielectric 211: Waveguide 212: RF power supply 301: Film formation chamber 302: Substrate 303: Substrate support 304: Exhaust pipe 305: Target electrode 306: Generate magnetron magnetic field Magnets to be driven 307: Gas introduction pipe 308: DC power supply 401: Film formation chamber 402: Base 403: Support for base 402 404: Exhaust pipe 405: 1 of the gas introduction pipe 406: second gas introduction pipe 407: dielectric 408: waveguide

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location H01L 21/31 H01L 21/31 D

Claims (16)

[Claims] 1. A film forming chamber including a holder for holding a coated substrate, an electrode on which a sputtering target is mounted, means for applying DC or high-frequency power to the electrode, and a gas supplied to the film forming chamber. Means for supplying, means for exhausting from the film forming chamber, means for supplying microwave power to the film forming chamber through an endless annular waveguide, introducing a gas into the film forming chamber, A plasma is generated by microwave power introduced through an endless annular waveguide and applied to a sputtering target electrode to control a hydrogen content incorporated in the thin film to form a thin film on a coated substrate. A thin film forming method. 2. The thin film forming method according to claim 1, wherein the control of the content of hydrogen incorporated in the thin film is performed by changing a gas flow rate / sputtering power. 3. The method according to claim 1, wherein the waveguide is an endless annular waveguide with a slot. 4. The means for supplying a gas includes a step of introducing a first gas mainly contributing to sputtering from a vicinity of a target, and a step of not reacting with sputtered particles and forming a film by plasma alone. 2. The method according to claim 1, further comprising the steps of: introducing a second gas from the vicinity of the endless annular waveguide; and introducing a third gas for forming a film by plasma alone from the vicinity of the base. 4. The method for forming a thin film according to any one of the above items 3. 5. The thin film forming method according to claim 1, wherein Ar is used as said first gas. 6. The thin film forming method according to claim 1, wherein N2 is used as said second gas. 7. The thin film forming method according to claim 1, wherein O2 is used as said second gas. 8. The method according to claim 1, wherein SiH4 is used as the third gas. 9. The method according to claim 1, wherein an organic aluminum is used as the third gas. 10. The thin film forming method according to claim 1, wherein a direct current or a high frequency bias is applied to said holder. 11. The method according to claim 1, wherein Si is used as the target. 12. The thin film forming method according to claim 1, wherein Al is used as said target. 13. A film forming chamber including a holder for holding a coated substrate, an electrode on which a sputtering target is mounted, means for applying DC or high-frequency power to the electrode, and a gas supplied to the film forming chamber. A thin film forming apparatus comprising: a supplying unit; a unit for exhausting gas from the film forming chamber; and a unit for supplying microwave power to the film forming chamber via a slotted endless annular waveguide. 14. A gas supply means comprising: a step of introducing a first gas mainly contributing to sputtering from the vicinity of a target; and a step of not reacting with sputtered particles and forming a film alone by plasma. 14. The method according to claim 13, further comprising a step of introducing the second gas from the vicinity of the endless annular waveguide and a step of introducing a third gas for forming a film by plasma alone from the vicinity of the base. Thin film forming equipment. 15. The thin film forming apparatus according to claim 13, wherein said target electrode is formed of Si. 16. The thin film forming apparatus according to claim 13, wherein said target electrode is formed of Al.