JPH0936071A - Method and device for polishing plane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a means for polishing the surface of a workpiece at a constant high polishing speed. SOLUTION: Such insulation film as semiconductor oxide film and semiconductor nitride film which are workpieces 9 and semiconductor substrates 111 , 112 ,... such as silicon or a metal substrate such as aluminum, copper, and iron are pressed a polishing sheet 2 provided on the upper surface of a rotary table 1 and the rotary table 1 is rotated while supplying a polishing liquid 8 to the polishing sheet, thus polishing the workpieces 9. A polishing liquid containing such polishing particles as silicon oxide, aluminum oxide, cerium oxide, and zirconium oxide whose amount of oxygen is smaller than a chemical stoichiometric value is used and a polishing liquid containing a polishing particle where a constituent with a lower electronegativity than the oxygen of, for example, nitrogen and a constituent with a higher electronegativity than the oxygen of, for example, fluorine is contained is used at least on the surface of the polishing particles. An electromagnetic wave is generated on the surface of the polishing sheet or a potential is applied between the polishing sheet and the workpieces for polishing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface polishing method and a surface polishing apparatus for processing a substrate having an interlayer insulating film such as a semiconductor oxide film or a semiconductor nitride film on its surface. In order to meet the demand for higher integration of semiconductor integrated circuit devices, there is a demand for a technique for flattening the surface of an interlayer insulating film in order to miniaturize wiring and make it multilayer.

Multi-layering of wiring means that after forming one layer of wiring, an insulating film is formed on the wiring, and a step of further forming wiring on the insulating film is repeated.
For example, in an integrated circuit device in which an MPU (microprocessor unit) and a drive integrated circuit are integrated, the wiring density varies depending on the location of each integrated circuit, and thus a step is formed after the interlayer insulating film is formed.

FIG. 4 is an explanatory view of flattening an interlayer insulating film of an integrated circuit device. FIG. 4A shows a cross section before the flattening process.
(B) shows a cross section after the flattening process. In this figure, 61 is a semiconductor substrate, 62 ₁ is a plate electrode, and 62 ₂
Is a high-density wiring, 62 ₃ is a low-density wiring, and 63 is an interlayer insulating film.

In this integrated circuit device, on the semiconductor substrate 61 on which necessary elements are formed by a wafer process, a first layer flat plate electrode 62 ₁ and high-density wiring are provided with an insulating film interposed if necessary. 62 ₂ and low-density wiring 62 ₃ are formed, and a first interlayer insulating film 63 is formed thereon. Following this, a second layer wiring is formed on the first interlayer insulating film 63, and if necessary, a second interlayer insulating film is further formed thereon, and a third layer is formed thereon. Wiring is formed.

At this time, the interlayer insulating film 63 is usually formed by CVD.
Although deposited by (chemical vapor deposition), the interlayer insulating film 63 becomes thicker on the flat plate electrode 62 ₁ and the high-density wiring 62 ₂ and becomes thinner on the low-density wiring 62 _3. Because of the tendency, a step is formed between the flat plate electrode 62 ₁ , the high-density wiring 62 _2, and the low-density wiring 62 ₃ as shown in FIG.

Therefore, in order to further form wiring on the interlayer insulating film 63, it is necessary to flatten this step. If the wiring of the second layer is formed without flattening the surface of the interlayer insulating film 63, disconnection is likely to occur at the step portion, and the manufacturing yield of the semiconductor integrated circuit device is reduced.

As a method of flattening the interlayer insulating film 63, there is a method of melting the interlayer insulating film 63 to mitigate the step, etc., but depending on these methods, as shown in FIG. 4 (B). In addition, the steps cannot be flattened sufficiently,
The polishing technique is most suitable in terms of process consistency and cost.

[0008]

2. Description of the Related Art FIG. 5 is an explanatory view of the configuration of a conventional surface polishing apparatus. In this figure, 71 is a rotary table, 72
Is a polishing sheet, 73 is a machine frame, 74 is a head pressing rod, 75
Is a head, 76 is a template, 77 is an abrasive supply pipe,
Reference numeral 78 is a polishing liquid, 79 is a workpiece, and 80 is an interlayer insulating film.

The conventional flat polishing apparatus has a rotary table 71 having a polishing sheet 72 adhered on the upper surface thereof, and a head 75 facing the rotary table 71. The head 75 above the rotary table 71 is of the apparatus. With the machine frame 73,
It is vertically movable and supported so as to be rotated.

The head 75 faces the rotary table 71, and the template 7 surrounding the workpiece 79 is mounted on the surface on which the workpiece 79 having the interlayer insulating film 80 on the lower surface is mounted.
6 is fixed, and the workpiece 79 is the template 76.
It is fitted in a region surrounded by and is suction-fixed to the head 75.

In this flat polishing apparatus, a polishing liquid 78 containing a free polishing agent such as colloidal silica is applied to the rotary table 7.
1 is sprayed onto the polishing sheet 72 and the workpiece 79 is pressed against the polishing sheet 72, and the rotary table 71 is driven to rotate the polishing sheet 72 and the head 75 to rotate the workpiece 79. Grind.

Depending on the material of the workpiece 79 and the polishing conditions, the force for pressing the workpiece 79 against the polishing sheet 72, that is, the processing pressure, is placed on, for example, the weight of the head 75 or the head 75. The weight and the thrust of an air cylinder fixed to the machine frame 73 are used.

[0013]

However, the interlayer insulating film 8 is formed by the conventional planar polishing method.
When 0 is polished, the polishing rate per unit time is not constant, and, for example, when the polishing rate at the initial stage and the polishing rate at the final stage of polishing are compared, the final stage is slower, resulting in poor process controllability. An object of the present invention is to provide a surface polishing method and a surface polishing apparatus capable of polishing the surface of a workpiece at a constant polishing rate and a high polishing rate.

[0014]

In a flat surface polishing method according to the present invention, an insulating film formed on a workpiece and a semiconductor substrate or a metal substrate are pressed against a polishing sheet provided on the upper surface of a rotary table. A step of rotating the rotary table while polishing liquid is supplied to the polishing sheet to polish the surface of the workpiece is adopted.

In this case, the workpiece and the semiconductor substrate or metal substrate can be pressed against the polishing sheet at mutually independent timings.

Further, in the flat surface polishing apparatus according to the present invention, a rotary table having a polishing sheet on the upper surface thereof, means for rotating the rotary table, and the upper surface of the rotary table formed on the workpiece. A structure including a head that presses the insulating film and the semiconductor substrate or the metal substrate and a unit that supplies a polishing liquid to the polishing sheet is adopted.

In this case, the opening for accommodating the semiconductor substrate or the metal substrate is formed around the opening for accommodating the workpiece of the head for pressing the insulating film formed on the workpiece against the polishing sheet provided on the rotary table. The template may be provided.

Further, in another flat surface polishing apparatus according to the present invention, a rotary table having a polishing sheet on its upper surface,
Means for rotating the rotary table, a head for pressing an insulating film formed on a workpiece on the upper surface of the rotary table, a head for pressing a semiconductor substrate or a metal substrate on the upper surface of the rotary table, A structure provided with a means for supplying a polishing liquid to the polishing sheet was adopted.

In this case, the head for pressing the insulating film formed on the work and the head for pressing the semiconductor substrate or the metal substrate are pressed against the polishing sheet at mutually independent timings. be able to.

Further, in another surface polishing method according to the present invention, the amount of oxygen in at least any one of silicon oxide, aluminum oxide, cerium oxide and zirconium oxide is set to be less than the stoichiometric value. A step of polishing a workpiece using a polishing liquid, a polishing liquid containing a component having an electronegativity lower than oxygen, or a polishing liquid containing a component having an electronegativity lower than oxygen was adopted.

Further, in another flat surface polishing method according to the present invention, a work piece is pressed and slid onto the polishing sheet while an electromagnetic field is generated in the vicinity of the surface of the polishing sheet to which the polishing liquid is supplied. A process of polishing the work piece by moving is adopted.

Further, in another flat surface polishing method according to the present invention, the workpiece is pressed against the polishing sheet in a state where a potential difference is applied between the polishing sheet to which the polishing liquid is supplied and the workpiece. A process of polishing the work piece by sliding is adopted.

Further, in another flat surface polishing apparatus according to the present invention, a rotary table provided with a polishing sheet, a head for pressing a workpiece on the upper surface of the polishing sheet, and a means for rotating the rotary table, A configuration is adopted in which a means for supplying a polishing liquid to the polishing sheet and a solenoid coil for generating an electromagnetic field are provided on the surface of the polishing sheet.

Further, in another flat surface polishing apparatus according to the present invention, a rotary table provided with a polishing sheet, a head for pressing an object to be processed on the upper surface of the polishing sheet, and means for rotating the rotary table, A configuration is adopted that includes a means for supplying a polishing liquid to the polishing sheet, a head for pressing the workpiece and a means for applying a potential difference between the polishing sheet.

The drawback of the conventional flat surface polishing method that the processing amount per unit time is not constant is mainly due to deterioration of the polishing ability of the polishing sheet. Usually, minute holes are formed on the surface of the polishing sheet, and the polishing agent is held in these holes, and the retained polishing agent moves with the rotation of the rotary table and is efficiently supplied to the surface of the workpiece. It

However, when the polishing is continued, the scraps scraped off are accumulated in the holes on the surface of the polishing sheet, the holes are clogged, and the abrasive cannot be held. Therefore, the polishing rate per unit time decreases as polishing is continued.

Therefore, if the clogging of the polishing sheet due to polishing dust can be eliminated, the polishing rate per unit time can be kept constant. In order to eliminate this clogging, a method is known in which the surface of the polishing sheet is dressed with a nylon brush every time the interlayer insulating film is polished once, but this is not practical because throughput decreases.

Also, in order to prevent a decrease in throughput,
A method of performing polishing and dressing at the same time can be considered, but if this is actually done, the effect of dressing is weak, so that clogging gradually occurs and the polishing rate gradually decreases. Therefore, in the flat surface polishing method and the flat surface polishing apparatus of the present invention, when polishing a workpiece, by polishing the semiconductor substrate or the metal substrate that does not cause clogging due to polishing dust of the polishing sheet, together with the workpiece. The principle is to prevent clogging of the polishing sheet.

[0029]

[Embodiment]

(First Embodiment) FIG. 1 is an explanatory view of the structure of a flat polishing apparatus of the first embodiment. In this figure, 1 is a rotary table,
2 is a polishing sheet, 3 is a machine frame, 4 is a head pressing rod, 5 is a head, 6 is a template, 6 ₁ , 6 ₂ , ... Are openings,
Reference numeral 7 is a polishing agent supply pipe, 8 is a polishing liquid, 9 is a work piece, 10 is an interlayer insulating film, and 11 ₁ , 11 ₂ , ... Are semiconductor substrates.

In the flat polishing apparatus of this embodiment, the rotary table 1 having the polishing sheet 2 adhered on its upper surface and the head 5 facing the rotary table 1 are provided. The head 5 above the rotary table 1 is The machine frame 3 of the apparatus is movably supported in the vertical direction and rotatably supported.

The head 5 faces the rotary table 1 and has openings 6 ₁ , 6 ₂ for accommodating semiconductor substrates 11 ₁ , 11 ₂ , ... Made of silicon on the surface on which the workpiece 9 is mounted.
6 _3, has a ..., are fixed template 6 which surrounds the workpiece 9, the workpiece 9 is fitted in the region surrounded by the template 6, the semiconductor substrate 11
₁ , 11 ₂ , ... Are openings 6 _{1 of the} template 6,
6 ₂ , ... It is fixed to the head 5 by being housed in it.

In this flat surface polishing apparatus, a polishing liquid 8 containing a free polishing agent such as colloidal silica is sprayed onto a polishing sheet 2 on a rotary table 1 by a polishing agent supply pipe 7 to form a workpiece 9 and a semiconductor substrate. 11 _1, 11 _2, pressed against the ... into abrasive sheet 2, by driving the rotary table 1, the head 5 with the rotation of the abrasive sheet 2 also rotates to polish the workpiece 9.

The work 9 is used as a means for obtaining a force for pressing the work 9 against the polishing sheet 2, that is, a processing pressure.
Depending on the material and polishing conditions, the weight of the head 5, the weight placed on the head 5, the thrust of the air cylinder fixed to the machine frame 3, and the like can be used.

In this way, when polishing the interlayer insulating film 10 of a workpiece using a liquid containing a free abrasive such as colloidal silica, the free abrasive is mainly used to mechanically scrape off the interlayer insulating film. As it progresses, the scraped polishing dust is adsorbed on the surface of the polishing sheet 2, causing clogging of the polishing sheet 2.

However, the semiconductor substrates 11 ₁ , 1 are prepared by using an abrasive containing a free abrasive such as colloidal silica.
When 1 ₂ , ... Is polished, the polishing liquid 8 itself mainly chemically reacts with the semiconductor substrates 11 ₁ , 11 ₂ ,. Less scrap is generated. In addition, the semiconductor substrate 11
_1, 11 _2, ... and the polishing sheet 2 is to cause a strong interaction, polishing waste clogged are effectively washed away by the polishing liquid, easily removed.

The polishing conditions of this example are as follows. Material of polishing sheet ・ ・ ・ Polyurethane Abrasive agent ・ ・ ・ Colloidal silica Polishing pressure ・ ・ ・ 300g / cm ² Rotation rate ・ ・ ・ 60rpm

When the silicon oxide film is polished under the above polishing conditions without using a silicon substrate as a semiconductor substrate, the initial polishing rate is 400 Å / min. However, if polishing is continued continuously, 40 minutes later, 300Å / min
To decline. Next, using the same polishing agent and polishing the silicon substrate, which is a semiconductor substrate, for 20 minutes under the above conditions, the polishing rate was recovered to 400 Å / min.

In this embodiment, the silicon substrate is used as the semiconductor substrate, but other semiconductor substrates such as GaAs having reactivity with polishing particles made of metal oxide such as oxidization can be effectively used. In general, a semiconductor substrate is convenient because it can be manufactured using an established technique for reducing impurities which are harmful to a workpiece. Further, instead of the semiconductor substrate, a substrate made of a metal such as Al, Cu, Fe having reactivity such as oxidation can be used.

(Second Embodiment) FIG. 2 is a plan view of the second embodiment.
It is a structure explanatory view of a polishing device. In this figure, 21 is
Rotary table, 22 is a polishing sheet, 23₁, 23_TwoIs an opportunity
Frame, 24₁, 24_TwoIs the head pressing rod, 25₁, 25_TwoIs
Head, 26₁, 26 _TwoIs a template, 27 is an abrasive
Supply pipe, 28 is a polishing liquid, 29 is a work piece, 30 is an interlayer insulation
The edge film 31 is a semiconductor substrate.

In the flat surface polishing apparatus of this embodiment, a rotary table 21 having a polishing sheet 22 adhered on the upper surface thereof,
It has a rotary head 25 ₁ which has been opposed to the table 21, 25 _2, above the head of the rotary table 21 25 _1, 25 ₂
Is vertically movable and rotatably supported by machine frames 23 ₁ and 23 ₂ of the apparatus.

The head 25 ₁ is mounted on the rotary table 21.
A template 26 ₁ surrounding the work piece 29 is fixed to the surface of the head 25 _{1 on} which the work piece 29 is mounted, and the work piece 29 having the interlayer insulating film 30.
Is fitted into the area surrounded by the template 26 ₁ and fixed to the head 25 ₁ .

Further, the surface head 25 ₂ is opposed to the rotary table 21, in the head 25 ₂ for mounting a semiconductor substrate 31, template 26 ₂ surrounding the semiconductor substrate 31
Is fixed, and the semiconductor substrate 31 has the template 26
_The head 25 ₂ fitted in the area surrounded by ₂
Fixed to.

In this flat surface polishing apparatus, a polishing liquid 28 containing a free polishing agent such as colloidal silica is applied to the rotary table 2.
1 is sprayed onto the polishing sheet 22 and the interlayer insulating film 30 of the work piece 29 is pressed against the polishing sheet 22, the rotary table 21 is driven, and the head 25 ₁ rotates together with the rotation of the polishing sheet 22, The interlayer insulating film 30 of the work piece 29 is polished.

As described above, when the insulating film is processed by using the liquid containing the free abrasive such as colloidal silica, the free abrasive is mainly scraped off because the polishing mechanically scrapes the insulating film. The polishing dust is adsorbed on the surface of the polishing sheet 22 and causes the polishing sheet 22 to be clogged.

However, when the semiconductor substrate 31 is polished with an abrasive containing a free abrasive such as colloidal silica, the polishing solution itself mainly chemically reacts with the semiconductor substrate 31 to proceed with etching, so that the polishing sheet. Polishing debris that causes the clogging of 22 is unlikely to occur, and the semiconductor substrate 31 and the polishing sheet 22 cause a strong interaction, so that the clogged polishing debris is effectively washed away by the polishing liquid, and is easily To be removed. When the polishing conditions of this embodiment are the same as the polishing conditions of the first embodiment, the polishing rate decreased by polishing the workpiece can be recovered by polishing the semiconductor substrate.

(Third Embodiment) The workpiece is pressed against the polishing sheet attached to the upper surface of the rotating rotary table described in the first and second embodiments, and the colloidal is placed on the polishing sheet. A flat surface polishing apparatus that sprays a polishing liquid containing a free polishing agent such as silica and polishes it under uniform conditions and a flat surface polishing method using the same have a limited polishing rate and require a certain processing time. is there.

For example, when the interlayer insulating film is flattened, there is a problem that only a dozen or more semiconductor wafers can be processed per hour. As described above, in the ordinary flat surface polishing method, the reason why the polishing speed takes a certain amount of time is that the reactivity between the liquid containing the free abrasive such as silica (silicon dioxide) and the surface of the workpiece is relatively weak. Is.

For example, a general CV is used as an interlayer insulating film.
When the D silicon oxide film is polished with a free abrasive such as silica (silicon dioxide), the surface of the workpiece and the surface of the free abrasive are both electrically negative, and thus repel each other,
As a result, the reactivity is lowered and the polishing rate is lowered. The flat surface polishing apparatus and the flat surface polishing method of this embodiment have an object to provide a means capable of efficiently polishing a workpiece.

FIG. 3 is an explanatory view of the structure of the flat-surface polishing apparatus of the third embodiment. In this figure, 41 is a rotary table,
42 is a polishing sheet, 43 is a machine frame, 44 is a head pressing rod,
Reference numeral 45 is a head, 46 is a template, 47 is a polishing agent supply pipe, 48 is a polishing liquid, 49 is a workpiece, 50 is an interlayer insulating film, and 51 is a solenoid coil.

In the flat polishing apparatus of this embodiment, a rotary table 41 having a polishing sheet 42 adhered on the upper surface thereof,
A head 45 facing the rotary table 41 is provided. The head 45 above the rotary table 41 is movably supported in the vertical direction and rotatably supported by a machine frame 43 of the apparatus.

The head 45 is opposed to the rotary table 41, and a template 46 surrounding the workpiece 49 is fixed to the surface of the head 45 on which the workpiece 49 is mounted, and an interlayer insulating film 50 is provided. The workpiece 49 is fitted into the area surrounded by the template 46 and fixed to the head 45.

In this flat polishing apparatus, the polishing liquid 48 containing a free polishing agent such as colloidal silica is used for the rotary table 4.
1 is sprayed onto the polishing sheet 42 and the interlayer insulating film 50 of the work piece 49 is pressed against the polishing sheet 42, the rotary table 41 is driven, and the head 45 is rotated together with the rotation of the polishing sheet 42. The interlayer insulating film 50 of the workpiece 49 is polished.

In the surface polishing apparatus of this embodiment, when the rotary table 41 is driven to polish the workpiece 49, the solenoid coil 51 is provided in the vicinity of the head 45, and the solenoid coil 51 has a high frequency. By supplying the electric current, a strong electromagnetic field is generated inside the solenoid coil 51, that is, in the polishing sheet 42 near the head 45.

When a strong electromagnetic field is generated in this way, particles having a negative or positive charge are present in the polishing liquid 48 containing a free polishing agent such as silica. 48 is stirred vigorously. Therefore, the free abrasive such as silica strongly contacts the interlayer insulating film 50 of the workpiece 49, so that the reactivity is improved and the processing speed is remarkably improved.

In this embodiment, the workpiece 4
Although the description has been made assuming that the interlayer insulating film 50 of No. 9 is polished, the polishing rate can be improved also when polishing the surface of the workpiece 49 that does not have the interlayer insulating film 50.

(Fourth Embodiment) In the third embodiment, a strong electromagnetic field is generated in the polishing sheet 42 near the head 45 to vigorously agitate the polishing liquid 48 and improve the processing speed. In the embodiment, a potential difference is applied between the rotary table 41 and the head 45, and particles having a negative or positive charge existing in the polishing liquid 48 containing a free polishing agent such as silica are drawn out to the surface of the polishing sheet 42. ,
Alternatively, an alternating potential difference is applied between the rotary table 41 and the head 45, and particles having a negative or positive charge present in the polishing liquid 48 containing a free abrasive such as silica are vigorously stirred to release the silica or the like. The abrasive is strongly contacted with the interlayer insulating film 50 of the workpiece 49 to improve the reactivity and the processing speed.

In this embodiment, the workpiece 4
Although the description has been made assuming that the interlayer insulating film 50 of No. 9 is polished, the polishing rate can be improved also when polishing the surface of the workpiece 49 that does not have the interlayer insulating film 50.

(Fifth Embodiment) In the surface polishing method of this embodiment, a polishing liquid (including a lapping liquid) containing polishing particles of silicon oxide, aluminum oxide, cerium oxide, zirconium oxide, etc. is used for polishing. In the case of planar polishing an object, for example, a lapping liquid containing polishing particles formed by reactive sputter growth and having a smaller stoichiometric ratio of oxygen than an oxide having a normal stoichiometric ratio is used.

The stoichiometric ratio is represented by the ratio of the valence of metal to the valence of oxygen. For example, silicon oxide having a stoichiometric ratio is SiO ₂ , but in this embodiment SiO _x (x
The fine particles of <2) are used. Further, aluminum oxide having a stoichiometric ratio is Al ₂ O ₃ , but in this embodiment, fine particles of Al ₂ O _x (x <3) are used.

As described above, when the amount of oxygen in the polishing particles is less than the stoichiometric value, the negative charges on the surface of the polishing particles, which are metal oxides, are reduced, the repulsion between the polishing particles is suppressed, and the work piece is processed. The polishing particles are supplied to the surface of the object at a high density, and the polishing rate is improved.

(Sixth Embodiment) In the flat surface polishing method of this embodiment, a polishing liquid (including a lapping liquid) containing polishing particles of silicon oxide, aluminum oxide, cerium oxide, zirconium oxide or the like is used for processing. In the case of flat polishing an object, a polishing liquid containing polishing particles containing a component having a lower electronegativity than oxygen such as nitrogen is used.

As described above, when the abrasive particles containing a component having an electronegativity lower than that of oxygen such as nitrogen are used, the negative charge on the surface of the abrasive particles is reduced, and between the abrasive sheet and the abrasive particles,
Further, the repulsion between the polishing particles can be suppressed, and the polishing particles can be supplied to the surface of the workpiece at a high density to improve the polishing rate.

(Seventh Embodiment) In the flat surface polishing method of this embodiment, a polishing liquid (including a lapping liquid) containing polishing particles such as silicon oxide, aluminum oxide, cerium oxide and zirconium oxide is used for processing. When the object is flat-polished, fine particles containing a component having a higher electronegativity than oxygen such as fluorine are used.

As described above, by using fine particles containing a component having a higher electronegativity than oxygen such as fluorine, the negative charge on the surface of the polishing particles is increased, and an electric field is generated between the polishing sheet and the workpiece. To improve the polishing efficiency by flowing the abrasive particles toward the surface of the work piece or by vibrating the abrasive particles by applying an alternating electric field, increase the momentum of the abrasive particles to increase the polishing rate. Can be improved.

(Eighth Embodiment) In the flat surface polishing method of this embodiment, a polishing liquid (including a lapping liquid) containing polishing particles such as silicon oxide, aluminum oxide, cerium oxide and zirconium oxide is used for processing. When polishing an object, only on the surface layer of the polishing particles in the polishing liquid, a layer having a lower stoichiometric ratio of oxygen than an oxide having a normal stoichiometric ratio is formed, or a layer such as oxygen such as nitrogen is used. A layer containing a component having a low electronegativity is formed, or a layer containing a component having an electronegativity higher than oxygen such as fluorine is formed. As described above in the fifth, sixth, and seventh examples, the polishing rate can be improved only by subjecting the polishing particles to the surface treatment.

(Ninth Embodiment) In this embodiment, a solenoid coil is provided in the vicinity of the head supporting the workpiece of the third embodiment, and flat polishing is performed to generate a strong electromagnetic field in the polishing sheet near the head. The apparatus, or the surface polishing apparatus of the fourth embodiment, which gives a potential difference between the rotary table and the head supporting the workpiece, is provided with the SiO of the fifth embodiment.
_x (x <2), Al ₂ O _x (x <3), etc., containing abrasive particles in which the amount of oxygen is less than the stoichiometric value, and the component such as nitrogen in Example 6 having a lower electronegativity than oxygen. No abrasive particles, or abrasive particles containing a component having a higher electronegativity than oxygen such as fluorine of the seventh embodiment, and abrasive particles having the above-mentioned layer formed only on the surface of the eighth embodiment are used. .

By doing so, the polishing conditions can be optimized by using the most suitable polishing particles for the polishing apparatus.

In this example, the polishing rate when an abrasive containing fine particles of Si _9.5 O _0.5 was used was
Comparing the polishing rates in the case of using an ordinary polishing agent containing fine particles made of SiO ₂ , a several times improvement in the polishing rate was observed.

[0069]

As described above, according to the present invention,
A flat surface polishing method and a flat surface polishing apparatus capable of polishing an object to be processed such as an interlayer insulating film at a constant and high polishing rate can be provided, which greatly contributes to the field of manufacturing semiconductor integrated circuit devices.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a configuration of a flat surface polishing apparatus according to a first embodiment.

FIG. 2 is an explanatory diagram of a configuration of a flat surface polishing apparatus according to a second embodiment.

FIG. 3 is a structural explanatory view of a surface polishing apparatus of a third embodiment.

4A and 4B are explanatory views of planarization of an interlayer insulating film of an integrated circuit device, FIG. 4A illustrates a cross section before the planarization treatment, and FIG. 4B illustrates a cross section after the planarization treatment.

FIG. 5 is an explanatory diagram of a configuration of a conventional flat surface polishing apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 rotary table 2 polishing sheet 3 machine frame 4 head pressing rod 5 head 6 template 6 ₁ , 6 ₂ , ... opening 7 abrasive supply pipe 8 polishing liquid 9 work piece 10 interlayer insulating film 11 ₁ , 11 ₂ , ... ..Semiconductor substrate 21 Rotating table 22 Polishing sheet 23 ₁ , 23 ₂ Machine frame 24 ₁ , 24 ₂ Head pressing rod 25 ₁ , 25 ₂ Head 26 ₁ , 26 ₂ Template 27 Polishing agent supply pipe 28 Polishing liquid 29 Workpiece 30 Interlayer insulating film 31 Semiconductor substrate 41 Rotary table 42 Polishing sheet 43 Machine frame 44 Head pressing rod 45 Head 46 Template 47 Abrasive supply pipe 48 Polishing liquid 49 Workpiece 50 Interlayer insulating film 51 Solenoid coil

Claims (11)

[Claims] 1. A rotary table which presses an insulating film formed on a workpiece and a semiconductor substrate or a metal substrate against a polishing sheet provided on the upper surface of the rotary table and supplies a polishing liquid to the polishing sheet. A flat surface polishing method comprising rotating a surface of a workpiece to rotate the workpiece. 2. The surface polishing method according to claim 1, wherein the workpiece and the semiconductor substrate or the metal substrate are pressed against the polishing sheet at mutually independent timings. 3. A rotary table having a polishing sheet on its upper surface, a means for rotating the rotary table, and an insulating film formed on a workpiece and a semiconductor substrate or a metal substrate pressed against the upper surface of the rotary table. And a means for supplying a polishing liquid to the polishing sheet. 4. An opening for accommodating a semiconductor substrate or a metal substrate is provided around an opening for accommodating a workpiece of a head for pressing an insulating film formed on the workpiece against a polishing sheet provided on a rotary table. The surface polishing apparatus according to claim 3, wherein a template is provided. 5. A rotary table having a polishing sheet on its upper surface, a means for rotating the rotary table, a head for pressing an insulating film formed on a workpiece against the upper surface of the rotary table, and the rotary table. A flat polishing apparatus comprising: a head for pressing a semiconductor substrate or a metal substrate against the upper surface of a table; and means for supplying a polishing liquid to the polishing sheet. 6. A head for pressing an insulating film formed on a workpiece and a head for pressing a semiconductor substrate or a metal substrate are pressed against a polishing sheet at mutually independent timings. The flat surface polishing apparatus according to claim 5. 7. A polishing liquid containing at least any one of silicon oxide, aluminum oxide, cerium oxide, and zirconium oxide, a polishing liquid containing less than a stoichiometric amount of oxygen, and a component having a lower electronegativity than oxygen. A flat surface polishing method comprising polishing a workpiece using a polishing liquid contained therein or a polishing liquid containing a component having an electronegativity higher than oxygen. 8. A work piece is polished by pressing the work piece against the polishing sheet and sliding the work piece in a state where an electromagnetic field is generated near the surface of the polishing sheet to which the polishing liquid is supplied. A characteristic surface polishing method. 9. A work piece is polished by pressing the work piece against the polishing sheet and sliding the work piece with a potential difference applied between the work sheet and the polishing sheet supplied with the polishing liquid. A surface polishing method characterized by: 10. A rotary table provided with a polishing sheet,
The polishing sheet is provided with a head for pressing the workpiece on the upper surface, a means for rotating the rotary table, a means for supplying a polishing liquid to the polishing sheet, and a solenoid coil for generating an electromagnetic field on the surface of the polishing sheet. A flat polishing device characterized by the above. 11. A rotary table provided with a polishing sheet,
Between the head for pressing the work piece against the upper surface of the polishing sheet, the means for rotating the rotary table, the means for supplying a polishing liquid to the polishing sheet, and the head for pressing the work piece and the polishing sheet. A surface polishing apparatus comprising means for applying a potential difference to the surface polishing apparatus.