JP3582026B2 - Planar polishing method and planar polishing apparatus - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a planar polishing method and a planar polishing apparatus for processing a substrate having a surface having an interlayer insulating film such as a semiconductor oxide film or a semiconductor nitride film.
In order to meet the demand for higher integration of semiconductor integrated circuit devices, there is a demand for a technology for flattening the surface of an interlayer insulating film in order to make wiring finer and multi-layered.
[0002]
Multi-layered wiring means that after forming one layer of wiring, an insulating film is formed thereon, and a step of further forming a wiring on the insulating film is repeated.
For example, in an integrated circuit device in which an MPU (microprocessor unit) and a driving integrated circuit are integrated, the wiring density differs depending on the location of each integrated circuit, so that a step occurs after an interlayer insulating film is formed.
[0003]
4A and 4B are explanatory views of the planarization of the interlayer insulating film of the integrated circuit device. FIG. 4A shows a cross section before the planarization processing, and FIG. 4B shows a cross section after the planarization processing.
In this figure, 61 is a semiconductor substrate, 62 ₁ planar electrodes, 62 ₂ high-density wiring, 62 ₃ low-density wiring, 63 denotes an interlayer insulating film.
[0004]
In this integrated circuit device, a first-layer plate-like electrode 62 ₁ , high-density wiring 62 ₂ , low density wiring 62 ₃ is formed, the first interlayer insulating film 63 is formed thereon.
Subsequently, 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. Is formed.
[0005]
At this time, the interlayer insulating film 63 is normally deposited by CVD (chemical vapor deposition), it becomes thick interlayer insulating film 63 on the planar electrodes 62 ₁ and high-density wiring 62 _2, low density wiring 62 since the interlayer insulating film 63 on the ₃ tends to become thinner, stepped between 4 as shown (a), the planar electrodes 62 ₁ and the high-density wiring 62 ₂ and the low-density wiring 62 ₃ Occurs.
[0006]
Therefore, in order to further form a wiring on the interlayer insulating film 63, it is necessary to flatten the 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, and the manufacturing yield of the semiconductor integrated circuit device will be reduced.
[0007]
As a method of flattening the interlayer insulating film 63, there is a method of melting the interlayer insulating film 63 to reduce a step, etc., but depending on these methods, as shown in FIG. Cannot be sufficiently flattened, and a polishing technique is most suitable in terms of process consistency, cost, and the like.
[0008]
[Prior art]
FIG. 5 is an explanatory view of the configuration of a conventional planar 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, 78 is a polishing liquid, and 79 is a workpiece. And 80 are interlayer insulating films.
[0009]
The conventional planar polishing apparatus includes a rotary table 71 having a polishing sheet 72 adhered to an upper surface thereof, and a head 75 opposed to the rotary table 71. A head 75 above the rotary table 71 is provided with a machine frame 73 of the apparatus. , And are supported so as to be movable in the vertical direction and to be rotated.
[0010]
The head 75 is opposed to the rotary table 71, and a template 76 surrounding the workpiece 79 is fixed to a surface on which a workpiece 79 having an interlayer insulating film 80 on its lower surface is mounted. It is fitted into a region surrounded by 76 and is suction-fixed to the head 75.
[0011]
In this planar polishing apparatus, a polishing liquid 78 containing a free abrasive such as colloidal silica is sprayed on a polishing sheet 72 on a rotary table 71 to press a workpiece 79 against the polishing sheet 72 and drive the rotary table 71. Then, the polishing sheet 72 is rotated and the head 75 is also rotated, and the workpiece 79 is polished.
[0012]
The force for pressing the workpiece 79 against the polishing sheet 72, that is, the weight of the head 75, the weight placed on the head 75, The thrust of the air cylinder fixed to the machine frame 73 is used.
[0013]
[Problems to be solved by the invention]
However, when the interlayer insulating film 80 is polished by the conventionally used planar polishing method, the reactivity between the polishing liquid 78 containing a free abrasive such as colloidal silica and the interlayer insulating film 80 is relatively weak. For example, there has been a problem that only several tens of workpieces 79 can be polished per hour .
An object of the present invention is to provide a planar polishing method and a planar polishing apparatus capable of polishing a surface of a workpiece at a high polishing rate.
[0020]
[Means for Solving the Problems]
In the planar polishing method and the planar polishing apparatus according to the present invention, as a method invention,
(1)
In a planar polishing method for polishing a workpiece using a polishing liquid containing at least one of silicon oxide, aluminum oxide, cerium oxide, and zirconium oxide, the amount of oxygen in the polishing particles is determined from a stoichiometric value. Characterized by reduced or
(2)
In a planar polishing method for polishing a workpiece using a polishing liquid containing at least one of silicon oxide, aluminum oxide, cerium oxide, and zirconium oxide, a component having a lower electronegativity than oxygen is polished. It is characterized by being included in, or,
(3)
In a state in which an alternating potential difference is given between the polishing sheet and the workpiece to which the polishing liquid is supplied, the workpiece is polished by pressing and sliding the workpiece on the polishing sheet,
And as an invention of a product,
(4)
A rotary table provided with a polishing sheet, a head for pressing a workpiece on the upper surface of the polishing sheet, a unit for rotating the rotary table, a unit for supplying a polishing liquid to the polishing sheet, It is characterized by comprising a head for pressing and a means for providing an alternating potential difference between the polishing sheet and the polishing sheet.
[0021]
In another planar polishing method according to the present invention, in a state where an electromagnetic field is generated near the surface of the polishing sheet to which the polishing liquid is supplied, the workpiece is pressed against the polishing sheet and slid. The step of polishing the workpiece is adopted.
[0022]
In another planar polishing method according to the present invention, in a state where a potential difference is given between a polishing sheet to which a polishing liquid is supplied and a workpiece, the workpiece is pressed against the polishing sheet and slid. Thus, a step of polishing the workpiece is adopted.
[0023]
In another planar polishing apparatus according to the present invention, there is provided a rotary table provided with a polishing sheet, a head for pressing a workpiece on an upper surface of the polishing sheet, means for rotating the rotary table, and a polishing sheet. And 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.
[0024]
In another planar polishing apparatus according to the present invention, there is provided a rotary table provided with a polishing sheet, a head for pressing a workpiece on an upper surface of the polishing sheet, means for rotating the rotary table, and a polishing sheet. And a means for supplying a polishing liquid to the workpiece and a means for applying a potential difference between the head for pressing the workpiece and the polishing sheet.
[0025]
The disadvantage of the conventional planar polishing method that the processing amount per unit time is not constant is mainly due to the deterioration of the polishing ability of the polishing sheet. Usually, fine holes are formed on the surface of the polishing sheet, and the polishing agent is held in these holes, and the held polishing agent moves with the rotation of the turntable, and is efficiently supplied to the surface of the workpiece. You.
[0026]
However, when the polishing is continued, the shavings scraped off are accumulated in the holes on the surface of the polishing sheet, the holes are clogged, the abrasive cannot be held, and the abrasive is efficiently applied to the surface of the workpiece. Since supply cannot be performed, the polishing rate per unit time decreases as polishing continues.
[0027]
Therefore, if the clogging of the polishing sheet due to the polishing debris can be eliminated, the polishing rate per unit time can always be kept constant.
In order to eliminate the clogging, a method of dressing the surface of the polishing sheet with a nylon brush every time the interlayer insulating film is polished once is known, but is not practical because the throughput is reduced.
[0028]
In order to prevent a decrease in throughput, a method in which polishing and dressing are performed at the same time is conceivable. However, when this is actually performed, clogging occurs gradually because the effect of the dress is weak, and the polishing rate gradually decreases.
Therefore, in the planar polishing method and the planar polishing apparatus of the present invention, when polishing a workpiece, by polishing a semiconductor substrate or a metal substrate that does not cause clogging with polishing debris of a 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 configuration of the planar polishing apparatus of the first embodiment.
In this figure, 1 is a turntable, 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 ,... tubes, 8 polishing liquid, 9 workpiece, the interlayer insulating film _10, 11 1, ₁₁ 2, ... is a semiconductor substrate.
[0030]
The planar polishing apparatus of this embodiment has a rotary table 1 on which an abrasive sheet 2 is adhered on an upper surface, and a head 5 opposed to the rotary table 1, and the head 5 above the rotary table 1 is a machine of the apparatus. The frame 3 is vertically rotatable and rotatably supported.
[0031]
The head 5 faces the rotary table 1 and has openings 6 ₁ , 6 ₂ , 6 ₃ ,... For accommodating semiconductor substrates 11 ₁ , 11 ₂ ,. , And the template 6 surrounding the workpiece 9 is fixed, and the workpiece 9 is fitted into an area surrounded by the template 6, and the semiconductor substrates 11 ₁ , 11 ₂ ,. Are fixed to the head 5 by being housed in the openings 6 ₁ , 6 ₂ ,.
[0032]
In this flat-surface polishing apparatus, a polishing liquid 8 containing a free abrasive such as colloidal silica is sprayed on a polishing sheet 2 on a rotary table 1 by an abrasive supply pipe 7 so that a workpiece 9 and semiconductor substrates 11 ₁ , 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.
[0033]
The force for pressing the workpiece 9 against the polishing sheet 2, that is, the weight of the head 5 or the weight placed on the head 5 depends on the material and the polishing conditions of the workpiece 9 as means for obtaining the processing pressure. The weight, the thrust of an air cylinder fixed to the machine frame 3 and the like can be used.
[0034]
As described above, when the interlayer insulating film 10 of the workpiece is polished using a liquid containing a free abrasive such as colloidal silica, mainly, the free abrasive mechanically scrapes the interlayer insulating film. In addition, the shaved polishing debris is adsorbed on the surface of the polishing sheet 2 and causes the polishing sheet 2 to be clogged.
[0035]
However, the semiconductor substrate ₁₁ 1 using an abrasive containing loose abrasive agent such as colloidal silica, ₁₁ 2, when polishing a ... mainly polishing liquid 8 itself semiconductor substrate ₁₁ 1, ₁₁ 2,... And chemically Since the etching proceeds due to the reactive reaction, polishing dust that clogs the polishing sheet 2 is less likely to be generated.
Further, since the semiconductor substrates 11 ₁ , 11 ₂ ,... And the polishing sheet 2 cause a strong interaction, the clogged polishing debris is effectively washed away by the polishing liquid and easily removed.
[0036]
The polishing conditions of this example are as follows.
Polishing sheet material: Polyurethane abrasive: Colloidal silica polishing pressure: 300 g / cm ²
Number of rotations: 60 rpm
[0037]
When the silicon oxide film is polished without using a silicon substrate as the semiconductor substrate under the above polishing conditions, the initial polishing rate is 400 ° / min. To decline.
Next, when the same abrasive was used and the silicon substrate as the semiconductor substrate was polished for 20 minutes under the above conditions, the polishing rate was restored to 400 ° / min.
[0038]
In this embodiment, a silicon substrate is used as a semiconductor substrate. However, other semiconductor substrates such as GaAs having reactivity with abrasive particles made of metal oxide such as oxide can be effectively used.
In general, the use of a semiconductor substrate is advantageous because it can be manufactured using a technique for reducing impurities which are harmful to an object to be processed.
Further, instead of the semiconductor substrate, a substrate made of a metal such as Al, Cu, and Fe having reactivity such as oxidation can be used.
[0039]
(Second embodiment)
FIG. 2 is a diagram illustrating the configuration of the planar polishing apparatus according to the second embodiment.
In this figure, the rotary table 21, the abrasive sheet _22, 23 1, 23 ₂ machine _frame, 24 1, 24 ₂ head pressing _lever, 25 1, 25 _{2 heads,} 26 1, 26 ₂ templates 27 Is a polishing agent supply pipe, 28 is a polishing liquid, 29 is a workpiece, 30 is an interlayer insulating film, and 31 is a semiconductor substrate.
[0040]
In surface polishing apparatus of this embodiment includes a rotary table 21 which polishing sheet 22 is attached to the upper surface, has a head 25 _1, 25 ₂ which is opposed to the rotating table 21, the upper head 25 of the rotary table 21 _1, 25 ₂ by the machine frame ₂₃ 1, 23 ₂ of the device, it is movable in the vertical direction, and is rotatably supported.
[0041]
Then, the head 25 ₁ is opposed to the rotating table 21, on the surface for mounting the workpiece 29 in the head 25 _1, are fixed template 26 ₁ surrounding the workpiece 29, having an interlayer insulating film 30 workpiece 29 is fitted in the region surrounded by the template 26 ₁ is fixed to the head 25 _1.
[0042]
The head 25 ₂ is opposed to the rotating table 21, the surface mounting the semiconductor substrate 31 in the head 25 _2, are fixed template 26 ₂ surrounding the semiconductor substrate 31, the semiconductor substrate 31 is a template 26 ₂ fitted surrounded area is fixed to the head 25 _2.
[0043]
In this planar polishing apparatus, a polishing liquid 28 containing a free abrasive such as colloidal silica is sprayed on the polishing sheet 22 on the turntable 21 to press the interlayer insulating film 30 of the workpiece 29 against the polishing sheet 22, It drives the rotary table 21, the head 25 ₁ with the rotation of the abrasive sheet 22 be rotated to polish the interlayer insulating film 30 of the workpiece 29.
[0044]
As described above, when processing an insulating film using a liquid containing a free abrasive such as colloidal silica, mainly, the polishing in which the free abrasive mechanically scrapes the insulating film progresses. It is adsorbed on the surface of the polishing sheet 22 and causes clogging of the polishing sheet 22.
[0045]
However, when the semiconductor substrate 31 is polished with an abrasive containing a free abrasive such as colloidal silica, the polishing liquid itself reacts chemically with the semiconductor substrate 31 and the etching progresses. Polishing debris that causes clogging is less likely to be generated, and the semiconductor substrate 31 and the polishing sheet 22 have a strong interaction. Therefore, the clogged polishing debris is effectively washed away by the polishing liquid and easily removed.
When the polishing conditions in this embodiment are the same as those in the first embodiment, the polishing rate reduced by polishing the workpiece can be recovered by polishing the semiconductor substrate.
[0046]
(Third embodiment)
The workpiece is pressed against the polishing sheet stuck on the upper surface of the rotating rotary table described in the first and second embodiments, and the polishing sheet contains a free abrasive such as colloidal silica on the polishing sheet. A flat surface polishing apparatus and a flat surface polishing method using the same, which scatter liquid and polish under uniform conditions, have a limit in the polishing rate and require a certain amount of processing time.
[0047]
For example, when the interlayer insulating film is flattened, there is a problem that only ten and several semiconductor wafers can be processed per hour.
As described above, the reason why the polishing rate takes a certain amount of time in the ordinary planar polishing method is because the reactivity between the liquid containing a free abrasive such as silica (silicon dioxide) and the surface of the workpiece is relatively weak. It is.
[0048]
For example, when a general CVD silicon oxide film is polished with a free abrasive such as silica (silicon dioxide) as an interlayer insulating film, both the surface of the workpiece and the surface of the free abrasive are electrically negative. As a result, the reactivity decreases and the polishing rate decreases.
An object of the planar polishing apparatus and the planar polishing method of this embodiment is to provide a means capable of efficiently polishing a workpiece.
[0049]
FIG. 3 is an explanatory view of the configuration of the planar 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, 45 is a head, 46 is a template, 47 is an abrasive supply pipe, 48 is a polishing liquid, and 49 is a workpiece. , 50 are interlayer insulating films, and 51 is a solenoid coil.
[0050]
The planar polishing apparatus according to this embodiment includes a rotary table 41 having a polishing sheet 42 adhered to an upper surface thereof, and a head 45 opposed to the rotary table 41. The frame 43 is vertically rotatable and rotatably supported by the frame 43.
[0051]
The head 45 is opposed to the rotary table 41, and a template 46 surrounding the workpiece 49 is fixed to the head 45 on the surface on which the workpiece 49 is mounted, and the head 45 has an interlayer insulating film 50. 49 is fitted into the area surrounded by the template 46 and fixed to the head 45.
[0052]
In this planar polishing apparatus, a polishing liquid 48 containing a free abrasive such as colloidal silica is sprayed on the polishing sheet 42 on the turntable 41 to press the interlayer insulating film 50 of the workpiece 49 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 to polish the interlayer insulating film 50 of the workpiece 49.
[0053]
In the planar polishing apparatus of this embodiment, when the rotary table 41 is driven to polish the workpiece 49, a solenoid coil 51 is provided near the head 45, and a high-frequency current is supplied to the solenoid coil 51. By doing so, a strong electromagnetic field is generated inside the solenoid coil 51, that is, on the polishing sheet 42 near the head 45.
[0054]
When such a strong electromagnetic field is generated, the polishing liquid 48 containing a free abrasive such as silica contains particles having a negative or positive charge. Stirred.
Therefore, a 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.
[0055]
In this embodiment, the description has been made on the assumption that the interlayer insulating film 50 of the workpiece 49 is polished. However, when the surface of the workpiece 49 having no interlayer insulating film 50 is polished, it is necessary to improve the polishing rate. Can be.
[0056]
(Fourth embodiment)
In the third embodiment, a strong electromagnetic field is generated in the polishing sheet 42 near the head 45, whereby the polishing liquid 48 is vigorously agitated to improve the processing speed. By applying a potential difference between the heads 45, particles having negative or positive charges existing in the polishing liquid 48 containing a free abrasive such as silica are drawn out to the surface of the polishing sheet 42, or the rotary table 41 and the head 45 An alternating potential difference is applied between the particles, and the negatively or positively charged particles present in the polishing liquid 48 containing the free abrasive such as silica are vigorously stirred to strongly apply the free abrasive such as silica to the workpiece 49. Strongly in contact with the interlayer insulating film 50, thereby improving the reactivity and improving the processing speed.
[0057]
In this embodiment, the description has been made on the assumption that the interlayer insulating film 50 of the workpiece 49 is polished. However, when the surface of the workpiece 49 having no interlayer insulating film 50 is polished, it is necessary to improve the polishing rate. Can be.
[0058]
(Fifth embodiment)
In the planar polishing method of this embodiment, when the object to be polished is planar-polished using a polishing liquid (including a lapping liquid) containing polishing particles such as silicon oxide, aluminum oxide, cerium oxide, and zirconium oxide, for example, A lapping liquid formed by reactive sputter growth and containing abrasive particles having a lower stoichiometric ratio of oxygen than an oxide having a normal stoichiometric ratio is used.
[0059]
The stoichiometric ratio is expressed as the ratio between the valence of the metal and the valence of oxygen. For example, silicon oxide having a stoichiometric ratio is SiO ₂ , but in this embodiment, SiO _x (x <2) is used. Use fine particles.
The aluminum oxide having a stoichiometric ratio is Al ₂ O _{3. In} this embodiment, Al ₂ O _x (x <3) fine particles are used.
[0060]
Thus, when the amount of oxygen in the abrasive particles is smaller than the stoichiometric value, the negative charge on the surface of the abrasive particles, which is a metal oxide, is reduced, repulsion between the abrasive particles is suppressed, and the surface of the workpiece is reduced. The abrasive particles are supplied at a high density to improve the polishing rate.
[0061]
(Sixth embodiment)
In the planar polishing method of this embodiment, when the workpiece is planar polished using a polishing liquid (including a lapping liquid) containing polishing particles such as silicon oxide, aluminum oxide, cerium oxide, and zirconium oxide, nitrogen or the like is used. A polishing liquid containing abrasive particles containing a component having a lower electronegativity than oxygen is used.
[0062]
As described above, when the abrasive particles containing a component having a lower electronegativity than 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, and between the abrasive particles. Can be suppressed, and the polishing rate can be improved by supplying abrasive particles at high density to the surface of the workpiece.
[0063]
(Seventh embodiment)
In the planar polishing method of this embodiment, when the workpiece is planar-polished using a polishing liquid (including a lapping liquid) containing polishing particles such as silicon oxide, aluminum oxide, cerium oxide, and zirconium oxide, fluorine or the like is used. Fine particles containing a component having a higher electronegativity than oxygen are used.
[0064]
In this way, fine particles containing a component having a higher electronegativity than oxygen, such as fluorine, are used to increase the negative charge on the surface of the abrasive particles and apply an electric field between the abrasive sheet and the workpiece to polish the object. When the polishing efficiency is improved by causing the particles to flow toward the surface of the workpiece, or when the polishing particles are vibrated by applying an alternating electric field, the momentum of the polishing particles is increased to improve the polishing rate. Can be.
[0065]
(Eighth embodiment)
In the planar polishing method of this embodiment, when a workpiece is polished using a polishing liquid (including a lapping liquid) containing polishing particles such as silicon oxide, aluminum oxide, cerium oxide, zirconium oxide, etc. A layer having a smaller stoichiometric ratio of oxygen than an oxide having a normal stoichiometric ratio is formed only on the surface layer of the abrasive particles, or a component having a lower electronegativity than oxygen, such as nitrogen, is contained. Or a layer containing a component having a higher electronegativity than oxygen such as fluorine.
As described in the fifth embodiment, the sixth embodiment, and the seventh embodiment, the polishing rate can be improved only by performing the surface treatment on the abrasive particles.
[0066]
(Ninth embodiment)
In this embodiment, a solenoid polishing coil is provided in the vicinity of a head for supporting a workpiece to generate a strong electromagnetic field on a polishing sheet near the head according to the third embodiment. The amount of oxygen such as SiO _x (x <2) and Al ₂ O _x (x <3) of the fifth embodiment is applied to the planar polishing apparatus for applying a potential difference between the rotary table and the head supporting the workpiece. Abrasive particles smaller than the stoichiometric value, abrasive particles containing a component having a lower electronegativity than oxygen such as nitrogen in the sixth embodiment, or having an electronegativity lower than oxygen such as fluorine in the seventh embodiment. The abrasive particles containing a high component, the abrasive particles of the eighth embodiment having the above-mentioned layer formed only on the surface are used.
[0067]
In this case, the polishing conditions can be optimized by using the optimum polishing particles for the polishing apparatus.
[0068]
In this example, the polishing rate when using an abrasive containing fine particles composed of Si _9.5 O _{0.5 was set} to the polishing rate when using an abrasive containing ordinary fine particles composed of SiO _2. As a result, several times the polishing rate was improved.
[0069]
【The invention's effect】
As described above, according to the present invention, it is possible to provide a planar polishing method and a planar polishing apparatus capable of polishing a workpiece such as an interlayer insulating film at a constant and high polishing rate, and to manufacture a semiconductor integrated circuit device. It greatly contributes in the technical field.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of a configuration of a planar polishing apparatus according to a first embodiment.
FIG. 2 is an explanatory diagram of a configuration of a planar polishing apparatus according to a second embodiment.
FIG. 3 is an explanatory view of a configuration of a planar polishing apparatus according to a third embodiment.
FIGS. 4A and 4B are explanatory views of flattening an interlayer insulating film of an integrated circuit device, wherein FIG. 4A shows a cross section before the flattening process, and FIG. 4B shows a cross section after the flattening process.
FIG. 5 is an explanatory diagram of a configuration of a conventional planar polishing apparatus.
[Explanation of symbols]
Reference Signs List 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 workpiece 10 interlayer insulating film 11 ₁ , 11 ₂ ,. .. Semiconductor substrate 21 Rotary table 22 Polishing sheets 23 ₁ and 23 ₂ Machine frames 24 ₁ and 24 ₂ Head pressing rods 25 ₁ and 25 ₂ heads 26 ₁ and 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 (4)

In a planar polishing method for polishing a workpiece using a polishing liquid containing at least one of abrasive particles of silicon oxide, aluminum oxide, cerium oxide, and zirconium oxide, the amount of oxygen in the abrasive particles is determined from a stoichiometric value. A planar polishing method characterized in that it is reduced. In a planar polishing method for polishing a workpiece using a polishing liquid containing at least one of silicon oxide, aluminum oxide, cerium oxide, and zirconium oxide, a component having a lower electronegativity than oxygen is polished to particles. A planar polishing method characterized by including the following. Polishing a workpiece by pressing and sliding the workpiece against the polishing sheet in a state where an alternating potential difference is given between the polishing sheet to which the polishing liquid is supplied and the workpiece.
A planar polishing method characterized by the above-mentioned. A rotary table provided with a polishing sheet, a head for pressing a workpiece on the upper surface of the polishing sheet, a unit for rotating the rotary table, a unit for supplying a polishing liquid to the polishing sheet, Means for providing an alternating potential difference between the pressing head and the polishing sheet;
A planar polishing apparatus comprising:

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