JPH09219384A - Method and equipment for cleaning - Google Patents

Abstract

PROBLEM TO BE SOLVED: To remove foreign matters at the bottom of a contact hole without decreasing the reliability of a semiconductor device by processing the semiconductor device with cleaning liquid which has a specified viscosity and has a capacity of dissolving foreign matters and then processing the device to which the liquid is attached with a rinse. SOLUTION: In order to remove foreign matters 39 on a wafer wherein a contact hole 38 is formed, the wafer is first dipped in cleaning liquid for a specified period of time. Nextly, the wafer is dipped in a rinse for a specified period of time. The liquid has a viscosity of 50cp or above and 40cp or below. For example, the it is constituted of an organic or acid thickener, a hydrogen fluoride or hydrogen fluoride compound, and water. As for the organic thickener, ethylene glycol, glycerol, cresol, or phenol is used. And, for the acid thickener, phosphoric acid or sulfuric acid is used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning method and a cleaning method capable of removing foreign matters on the inner bottom of a contact hole, which may occur when a contact hole is formed in a semiconductor device, without lowering the reliability of the semiconductor device. It relates to the device.

[0002]

2. Description of the Related Art FIG. 9 is a diagram showing a structure of a conventional semiconductor device cleaning apparatus. In the figure, 1 is an overflow type cleaning tank in which a cleaning liquid 2 is stored, 3 is a wafer as a semiconductor device, 4 is a circulation line for circulating the cleaning liquid 2 in the cleaning tank 1, and a pump 5 and a filter 6 are provided. There is. 7
Is an overflow type rinse tank in which the rinse solution 8 is stored, 9 is a supply line for supplying the rinse solution 8 to the rinse tank 7, and 10 is a spin dryer.

Next, a method of cleaning the semiconductor device of the conventional cleaning apparatus having the above-mentioned structure will be described with reference to FIG. First, after forming the interlayer insulating film 12 and the wiring layer 13 on the semiconductor substrate or the lower wiring layer 11 shown in FIG. 10A, respectively, the patterned resist film 14 is formed.
To form Next, as shown in FIG. 10B, the interlayer insulating film 12 is etched by dry etching using the resist film 14 as a mask to penetrate the semiconductor substrate or the lower wiring layer 11 to form a contact hole 15. During this dry etching, the contact hole 15
A foreign substance 16 composed of a component equivalent to that of the interlayer insulating film 12 (for example, a substance that incorporates a component of an etching gas used for dry etching) remains on the inner bottom portion.

When removing the foreign matter 16 at the bottom of the contact hole 15 of the semiconductor device, the cleaning liquid 2 uses, for example, 1% hydrogen fluoride, and the operating temperature of the cleaning liquid 2 is room temperature (23.degree. It has a viscosity of 1 cp at 25 ° C.). Further, pure water is used as the rinse liquid 8, and the rinse liquid 8 is used at room temperature (23 ° C.
It has a viscosity of 1.76 to 1.77 cp at 25 ° C.

Next, the resist film 14 is removed. Next, the wafer 3 is immersed in the cleaning liquid 2 in the cleaning tank 1 in order to remove the foreign matter 16 on the wafer 3 having the contact holes 15 formed therein. Then, after the elapse of the desired time for the foreign matter 16 to be eluted into the cleaning liquid 2, the wafer 3 is pulled out from the cleaning tank 1. Next, the wafer 3 is dipped in the rinse liquid 8 in the rinse bath 7, and after a lapse of a desired time for removing the cleaning liquid 2 adhering to the wafer 3 with the rinse liquid 8, the wafer 3 is pulled out from the rinse bath 7. At this time, since both the cleaning liquid 2 and the rinse liquid 8 have low viscosities, the cleaning liquid 2 attached to the wafer 3 diffuses into the rinse liquid 8 in a few seconds. Next, the wafer 3 is dried by the spin dryer 10.

[0006]

Conventionally, if the foreign matter 16 at the bottom of the contact hole 15 remains as it is, the foreign matter 1
Wiring is performed at the inner bottom of the contact hole 15 other than the 6-formed locations, and the contact area of the contact is reduced.
The resistance with the upper wiring layer in the contact hole 15 becomes high, which causes malfunction of the device. From the above, it is necessary to completely remove the foreign matter 16.

Here, in order to completely remove the foreign matter 16, the wafer 3 must be immersed in the cleaning liquid 2 for a long time. At this time, the interlayer insulating film 12 having the same property as the foreign matter 16 is also etched at the same time. Therefore, when the wafer 3 is immersed in the cleaning liquid 2 for a long time, as shown in FIG. 11A, the foreign matter 16 is completely removed, but the contact hole 15 isotropically spreads.
5a. And such a contact hole 15
When the upper wiring layer 17 is laminated on a, it short-circuits with the wiring layer 13 as shown in FIG. 11B, which causes malfunction of the device.

As described above, considering that the contact hole 15a spreads isotropically, the contact hole 15a
If the margin between a and the wiring layer 13 is sufficient, the above problem does not occur, but there is a problem that it is difficult to secure a sufficient margin as the semiconductor device is miniaturized. It was

The present invention has been made to solve the above problems, and provides a cleaning method and a cleaning apparatus capable of removing foreign matter from the bottom of the contact hole without impairing the reliability of the semiconductor device. The purpose is to do.

[0010]

Means for Solving the Problems Claim 1 according to the present invention.
The cleaning method of No. 1 is a cleaning method of removing foreign matter at the bottom of the contact hole of a semiconductor device having a contact hole, and has a viscosity of 5 cp or more and 40 cp or less, and
The semiconductor device is treated with a cleaning liquid that dissolves foreign matter, and the semiconductor device to which the cleaning liquid is attached is treated with a rinse liquid.

According to a second aspect of the cleaning method of the present invention, an organic or acid thickener, hydrogen fluoride or a hydrogen fluoride compound, and water are added to the cleaning liquid of the first aspect. It is formed from and.

According to a third aspect of the cleaning method of the present invention, the thickening agent of the cleaning solution of the second aspect is an organic thickening agent of ethylene glycol, glycerin, cresol or phenol. Alternatively, it is formed with an acid thickener such as phosphoric acid or sulfuric acid.

A cleaning method according to a fourth aspect of the present invention is to control the viscosity of the cleaning liquid of the cleaning method according to any one of the first to third aspects by controlling the temperature of the cleaning liquid.

According to a fifth aspect of the cleaning method of the present invention, in the cleaning method of removing foreign matter on the inner bottom portion of the contact hole of the semiconductor device in which the contact hole is formed, the semiconductor device is treated with a cleaning liquid that dissolves the foreign matter. Process,
5 cp or more and 40 cp for semiconductor devices with cleaning liquid
It is treated with a rinse liquid having the following viscosity.

According to a sixth aspect of the cleaning method of the present invention, the rinse liquid of the fifth aspect of the cleaning method is formed with 100% alcohol.

According to a seventh aspect of the cleaning method of the present invention, the rinse liquid of the sixth aspect is formed from any of ethylene glycol, phenol, ethanol and isopropyl alcohol.

The cleaning method according to claim 8 of the present invention controls the viscosity of the rinse liquid in the cleaning method according to any one of claims 5 to 7 by controlling the temperature of the rinse liquid. .

A cleaning method according to a ninth aspect of the present invention is the cleaning method according to any one of the first to eighth aspects, wherein the treatment with the rinse liquid is performed by rotating the semiconductor device. .

A cleaning apparatus according to a tenth aspect of the present invention is a cleaning apparatus for removing foreign matter from a bottom portion of a contact hole of a semiconductor device having a contact hole.
It is provided with a coating means for coating the semiconductor device with the cleaning liquid and a vaporizing means for evaporating the cleaning liquid.

According to the eleventh aspect of the cleaning device of the present invention, the vaporizing means of the tenth aspect comprises a heating device and a decompression device.

A cleaning device according to a twelfth aspect of the present invention is the cleaning device according to the tenth or eleventh aspect, further comprising a rinse liquid applying means for applying the rinse liquid to the semiconductor device, and after the cleaning liquid is evaporated. The rinse liquid is applied to the semiconductor device.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1. Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 is a diagram showing a configuration of a semiconductor device cleaning apparatus according to a first embodiment of the present invention. In the figure, 18 is an overflow type cleaning tank in which a cleaning solution 19 is stored, 20 is a wafer as a semiconductor device, 21 is a circulation line for circulating the cleaning solution 19 in the cleaning tank 18, and the cleaning solution 19 is supplied from the supply side of the cleaning tank 18. , A filter 22, a first heater 23, and a pump 24 are sequentially formed.
Reference numeral 25 is a first controller that controls the first heater 23.

26 is an overflow type rinse tank in which a rinse solution 27 is stored, and 28 is a rinse solution 2 in the rinse tank 26.
A filter 29, a second heater 30, and a pump 31 are sequentially formed from the supply side of the rinse liquid 27 in the rinse tank 26 in a circulation line that circulates 7. Reference numeral 32 is a second controller for controlling the second heater 30, and 33 is a spin dryer.

Next, the cleaning liquid 19 and the rinse liquid 27 used in the cleaning apparatus of the first embodiment configured as described above.
Will be described. The cleaning liquid 19 has a viscosity of 5 cp or more and 40 cp or less, and is composed of, for example, an organic or acid thickener, hydrogen fluoride or a hydrogen fluoride compound, and water. Examples of the organic thickener include ethylene glycol, glycerin, cresol or phenol, and examples of the acid thickener include phosphoric acid or sulfuric acid.

Further, the rinse liquid 27 is 5 cp or more and 40 cp
It has the following viscosity and is made of, for example, 100% alcohols. Alcohols include ethylene glycol, phenol, ethanol, and isopropyl alcohol.

Next, a method of cleaning the semiconductor device of the cleaning apparatus of the first embodiment using the cleaning liquid 19 and the rinse liquid 27 as described above will be described with reference to FIG. First,
As in the conventional case, as shown in FIG. 2A, after forming the interlayer insulating film 35 and the wiring layer 36 on the semiconductor substrate or the lower wiring layer 34, respectively, the patterned resist film 37 is formed. Next, as shown in FIG. 2B, the interlayer insulating film 35 is etched by dry etching using the resist film 37 as a mask to penetrate to the semiconductor substrate or the lower wiring layer 34, and a contact hole 38 is formed.
To form At the time of this dry etching, a foreign substance 39 having a component equivalent to that of the interlayer insulating film 35 (for example, a substance which takes in a component of an etching gas used for dry etching) remains at the bottom of the contact hole 38.

Next, the resist film 37 is removed. Next, the foreign matter 39 of the wafer 20 in which the contact hole 38 is formed
To remove the wafer 20 from the cleaning solution 1 in the cleaning tank 18.
Dip in 9. Then, after a desired time has elapsed, the wafer 20 is pulled out from the cleaning tank 18. Next, the wafer 20 is dipped in the rinse liquid 27 in the rinse tank 26 (FIG. 2C), and after a predetermined time elapses, the wafer 20 is pulled up from the rinse tank 26 (FIG. 2D). Next, the wafer 3 is spin-dried 33
Dry with.

Hereinafter, the cleaning liquid 1 for the wafer 20 described above
The predetermined time of immersion in 9 and the predetermined time of immersion in rinse liquid 27 will be described. Conventionally, in order to remove the foreign matter 39 on the bottom of the inside of the contact hole 38, the wafer 20 had to be immersed in the cleaning liquid 19 for a time period during which the foreign matter 39 was eluted into the cleaning liquid 19, but in the first embodiment, the foreign matter 39 remains in the cleaning liquid 19. The wafer 20 is pulled up from the cleaning liquid 19 before 39 is eluted.

Then, the wafer 20 is dipped in the rinse liquid 27. At this time, since the viscosities of both the cleaning liquid 19 and the rinsing liquid 27 have been low until now, the cleaning liquid 19 in the contact hole 38 has diffused into the rinsing liquid 27 within a few seconds. However, in the first embodiment, the cleaning liquid 19 and the rinsing liquid 27 are diffused. Since both 27 have a viscosity of 5 cp or more and 40 cp or less,
The cleaning liquid 19 in the contact hole 38 slowly diffuses into the rinse liquid 27. The process in which the cleaning liquid 19 in the contact hole 38 diffuses into the rinse liquid 27 is
As shown in FIG. 3, when the wafer 20 is lifted from the cleaning tank 18, as shown by the alternate long and short dash line, the contact hole 38
The concentration of the cleaning liquid 19 in the inside is almost the same as the concentration of the cleaning liquid 19 in the cleaning tank 18 from the bottom to the top of the contact hole 38.

Since the cleaning liquid 19 gradually diffuses into the rinse liquid 27 after a lapse of an arbitrary time, the concentration of the cleaning liquid 19 in the contact hole 38 becomes thin at the upper portion of the contact hole 38, as shown by the solid line. Since the rinse liquid 27 has not diffused at the bottom of the cleaning liquid 38, the concentration is almost the same as the concentration of the cleaning liquid 19 in the cleaning tank 18.

Finally, the contact hole 38
The concentration of the cleaning liquid 19 therein becomes 0 at all points.
In this way, since the concentration of the cleaning liquid 19 gradually decreases from the upper part in the contact hole 38, the foreign matter 39 elutes at the inner bottom part of the contact hole 38, but the interlayer insulating film 35 forms in the upper part of the contact hole 38. Etching stops. Therefore, the contact hole 38
The foreign substance 39 on the inner bottom can be removed without affecting other parts.

Since the viscosities of the cleaning liquid 19 and the rinse liquid 27 also change depending on the temperature, the temperatures of the first heater 23 and the second heater 30 are controlled by the first controller 25 and the second controller 32. It can be changed easily. The range of temperature control is room temperature (23 ° C to 25 ° C).
C.) to 100.degree. C. can be used. FIG. 12 presents some examples of changes in viscosity of the above-mentioned thickener and rinse liquid with temperature.

Further, although the contact hole 38 is opened by dry etching and is anisotropically etched, as the miniaturization progresses and the aspect ratio becomes large,
Due to various causes, as shown in FIG. 2B, the opening width of the contact hole 38 becomes narrower toward the bottom of the contact hole 38. However, since the concentration of the cleaning liquid 19 in the contact hole 38 is gradually thinned from the upper portion of the contact hole 38 as described above, the interlayer insulating film 35 on the sidewall of the contact hole 38 is also etched to reach the bottom portion of the contact hole 38. As a result, as shown in FIG. 2D, the opening width of the contact hole 38a can be similarly formed in the upper part and the bottom part of the contact hole 38a.

The phenomenon described above, that is, controlling the diffusion rate of the cleaning liquid 19 into the rinse liquid 27 according to the size of the foreign matter 39 at the bottom of the contact hole 38 is used. Therefore, the viscosities of the cleaning liquid 19 and the rinse liquid 27 are appropriately changed in consideration of the state of the foreign matter 39 at the bottom of the inside of the contact hole 38 of the semiconductor device and the shape of the contact hole 38, so that the cleaning liquid 19 changes to the rinse liquid 27. Control the diffusion rate. Cleaning liquid 1 that can be controlled in this way
The viscosity of the cleaning liquid 19 and the rinse liquid 27 needs to be 5 cp or more, and the viscosity of the cleaning liquid 19 and the rinse liquid 27 that can enter the bottom of the contact hole 38 is 40 c.
It becomes p or less.

In the cleaning method of the first embodiment performed as described above, the viscosities of the cleaning liquid 19 and the rinse liquid 27 are set according to the state of the foreign matter 39 at the bottom inside the contact hole 38 of the semiconductor device, and the foreign matter 39 is removed. Can be performed without affecting other parts. Further, at that time, the shape of the contact hole 38 can be controlled.

In the first embodiment described above, the cleaning liquid 19 and the rinsing liquid 27 both have the viscosity of 5 cp or more and 40 cp or less, but the present invention is not limited to this, and only one of them has the viscosity of 5 cp or more and 40 cp or less. It goes without saying that the same effect can be obtained even if the above is performed.

Embodiment 2 FIG. 4 is a diagram showing a cleaning device according to a second embodiment of the present invention. In the figure, 40 is a chamber, 41 and 42 are pipes and pumps for exhausting the inside of the chamber 40, and 43 is a support table provided in the chamber 40.
4 is supported and rotated by the drive device 45. Reference numeral 46 is a vat for receiving the chemical liquid applied on the wafer 44, and 47 is a drain line for discharging the drainage of the vat 46 to the outside of the chamber 40.

A cleaning liquid tank 48 stores a cleaning liquid 49, a pump 50 for delivering the cleaning liquid 49 from the cleaning liquid tank 48 to a nozzle 51 in the chamber 40, and 52.
The nozzle 5 to apply the cleaning liquid 49 onto the wafer 44.
1 is a moving device, 53 is a rinse liquid tank in which the rinse liquid 54 is stored, 55 is a pump for delivering the rinse liquid 54 from the rinse liquid tank 53 to the nozzle 56 in the chamber 40, and 57 is the rinse liquid 54 Is a moving device that moves a nozzle 56 to coat the wafer 44 on the wafer 44.

Next, the operation of the cleaning apparatus according to the second embodiment having the above structure will be described. First, cleaning liquid 4
9 and the rinse liquid 54 are the same as those in the first embodiment. Next, in order to remove the foreign matter on the bottom of the contact hole of the semiconductor device, the wafer 44 is supported by
3 on the upper surface. Next, the drive unit 45 is used to support the support base 43.
To rotate the wafer 44. Then, when the wafer 44 reaches an appropriate rotation speed, the nozzle 51 is moved to an appropriate position on the wafer 44 by the moving device 52.

Next, the cleaning liquid 49 is delivered from the nozzle 51 using the pump 50, and is applied onto the wafer 44. After a predetermined time has elapsed, the pump 50 stops the delivery of the cleaning liquid 49. Next, the nozzle 51 is moved by the moving device 52,
Instead, the nozzle 56 is moved by the moving device 57 to the wafer 44.
Move to the appropriate position above. Next, the rinse liquid 54 is delivered from the nozzle 56 using the pump 55, and is applied onto the wafer 44. After the lapse of a predetermined time, the pump 55 stops the delivery of the rinse liquid 54. Then, the drive device 45 increases the rotation speed of the support base 43 to increase the rotation speed of the wafer 44 to perform drying.

The operation of the cleaning liquid 49 and the rinsing liquid 54, which are different from those in the first embodiment, of the above-described operation will be described. Unlike the first embodiment, the cleaning liquid 49 and the rinse liquid 54 are applied by rotating the wafer 44.
Therefore, since the flow rate of the rinse liquid 54 is controlled by the rotation speed of the wafer 44, the diffusion speed of the cleaning liquid 49 in the contact hole into the rinse liquid 54 is also the wafer 44.
Will be controlled by the rotation of.

Therefore, by controlling the rotation speed of the wafer 44, as in the case of the first embodiment, the removal of the foreign matter from the inner bottom portion of the contact hole can be performed without affecting other portions. It can be carried out. Further, if the shape of the contact hole is taken into consideration, the opening widths at the top and bottom of the contact hole can be similarly formed.

In the cleaning method of the second embodiment performed as described above, the viscosities of the cleaning liquid 49 and the rinsing liquid 54 are set according to the state of the foreign matter in the bottom of the contact hole of the semiconductor device, and the rinsing liquid 54 is applied. By controlling the rotation speed of the wafer 44 at this time, the foreign matter can be removed without affecting other parts. Further, at that time, the shape of the contact hole can be controlled.

Although FIG. 4 shows the single-wafer cleaning apparatus, the present invention is not limited to this, and a batch-type cleaning apparatus as shown in FIG. Only the structure of FIG. 5 different from that of FIG. 4 will be described. The wafers 44a, 44b, 44c are set in the cassette 58 rotated by the drive unit 45. Further, nozzles 51a and 56a provided with a plurality of pores corresponding to the wafers 44a, 44b and 44c are provided respectively, and the cleaning liquid 49 and the rinse liquid 54 can be applied to the wafers 44a, 44b and 44c, respectively. Has been done.

Embodiment 3 FIG. 6 is a diagram showing the configuration of the cleaning device according to the third embodiment of the present invention. In the figure, 59 is a chamber, 60 and 61 are pipes and pumps for exhausting the inside of the chamber 59, and 62 is a chamber 59.
A support table provided inside supports a wafer 63 as a semiconductor device on its upper surface, and is rotated by a driving device 64. 6
Reference numeral 5 denotes a bat for receiving the chemical liquid applied on the wafer 63, 6
6 is a drain line for draining the drainage of the vat 65 to the outside of the chamber 59.

67 is a cleaning liquid tank 67, 69 in which a cleaning liquid 68 made of, for example, 0.5% hydrogen fluoride aqueous solution is stored.
Is a pump for delivering the cleaning liquid 68 to the nozzle 70 in the chamber 59, 71 is a moving device for moving the nozzle 70 to apply the cleaning liquid 68 onto the wafer 63, and 72 is a vaporizing means for evaporating the cleaning liquid 68 of the wafer 68. As a heating lamp.

Next, a cleaning method of the third embodiment having the above-mentioned structure will be described with reference to FIGS.
First, similarly to the first embodiment, the interlayer insulating film 35 is etched by dry etching to penetrate the semiconductor substrate or the lower wiring layer 34 to form the contact hole 38. At the time of this dry etching, a foreign substance 39 composed of the same component as that of the interlayer insulating film 35 remains on the bottom of the contact hole 38.

Next, the wafer 63 is placed on the upper surface of the support base 62 in order to remove the foreign matter 39 on the wafer 63 having the contact holes 38 formed therein. Next, the support base 62 is rotated by the driving device 64, and the wafer 63 is rotated. Then, when the wafer 63 reaches an appropriate rotation speed, the nozzle 70 is moved to an appropriate position on the wafer 63 by the moving device 71.

Next, the cleaning liquid 68 is delivered from the nozzle 70 using the pump 69 and applied onto the wafer 63. next,
The nozzle 70 is moved from above the wafer 63 by the moving device 71. Next, the wafer 63 is heated to about 100 ° C. by the heating lamp 72 to evaporate the cleaning liquid 68 on the wafer 63 (FIG. 7A). At this time, if the evaporation rate of the cleaning liquid 68 is controlled, as shown in FIG.
The foreign material 39 will be removed.

The control of the evaporation rate of the cleaning liquid 68 will be described below. Since the cleaning liquid 68 is removed from the wafer 63 by evaporation, the etching amount of the cleaning liquid 68 in the contact hole 38 is, for example, as shown in FIG.
As shown in, it can be adjusted by controlling the evaporation rate of the cleaning liquid 68. Therefore, the foreign matter 39 is eluted at the bottom inside the contact hole 38, and the etching of the interlayer insulating film 35 does not proceed above the contact hole 38. Then, the foreign matter 39 eluted in the cleaning liquid 68 also evaporates at the same time. Therefore, the foreign matter 39 at the bottom of the contact hole 38 can be removed without any other influence.

Further, although the contact hole 38 is opened by dry etching and is anisotropically etched, as the miniaturization progresses and the aspect ratio becomes large,
Due to various causes, as shown in FIG. 7A, the opening width of the contact hole 38 becomes narrower toward the bottom of the contact hole 38. However, as described above, the interface of the cleaning liquid 68 in the contact hole 38 gradually lowers from the upper portion of the contact hole 38, so that the interlayer insulating film 35 on the sidewall of the contact hole 38 also contacts the contact hole 3.
As shown in FIG.
As shown in (b), the opening width of the contact hole 38b can be similarly formed in the upper portion and the bottom portion of the contact hole 38b.

In the cleaning apparatus of the third embodiment having the above-described structure, the evaporation rate of the cleaning liquid 68 is set according to the state of the foreign matter 39 at the bottom inside the contact hole 38 of the semiconductor device, and the foreign matter 39 is removed by another method. It can be done without affecting the location. At that time, contact hole 3
The shape of 8 can also be controlled.

In the third embodiment, the vaporizing means for evaporating the cleaning liquid 68 is performed by the heating lamp 72. However, the present invention is not limited to this, and the cleaning liquid is reduced by reducing the atmospheric pressure in the chamber 59, for example. It goes without saying that the boiling point of 68 may be lowered and evaporated, and the same effect can be obtained by adding a heating lamp thereto.

In the third embodiment, the foreign matter 39 is eluted into the cleaning liquid 68, and the eluted foreign matter 39 is also evaporated at the same time when the cleaning liquid 68 is evaporated. There is a possibility of adhesion. Therefore, if the semiconductor device is rinsed with the rinse liquid after the evaporation of the cleaning liquid 68, the reprecipitated foreign matter can be surely removed.

[0055]

As described above, according to the first aspect of the present invention, in the cleaning method for removing the foreign matter on the bottom inside the contact hole of the semiconductor device in which the contact hole is formed,
The step of treating the semiconductor device with a cleaning liquid that has a viscosity of 5 cp or more and 40 cp or less and that dissolves foreign matter, and the semiconductor device to which the cleaning liquid is attached are treated with the rinse liquid. It is possible to provide a cleaning method capable of controlling the diffusion rate of the cleaning liquid in the contact hole into the rinse liquid according to the foreign matter on the bottom of the contact hole.

According to claim 2 of the present invention, the cleaning liquid of the cleaning method according to claim 1 is prepared from an organic or acid thickener, hydrogen fluoride or a hydrogen fluoride compound, and water. Since it is formed, it is possible to provide a cleaning method capable of easily obtaining a cleaning liquid having a desired viscosity.

According to a third aspect of the present invention, the thickening agent for the cleaning liquid of the second aspect is an organic thickening agent of ethylene glycol, glycerin, cresol or phenol, or Since it is formed with a phosphoric acid or sulfuric acid acid-based thickener, it is possible to provide a cleaning method capable of surely obtaining a cleaning liquid having a desired viscosity.

Further, according to claim 4 of the present invention, since the viscosity of the cleaning liquid of the cleaning method according to any one of claims 1 to 3 is controlled by the temperature of the cleaning liquid, the cleaning liquid having a desired viscosity is obtained. It is possible to provide a cleaning method that can be easily set.

According to a fifth aspect of the present invention, in the cleaning method for removing foreign matter on the inner bottom portion of the contact hole of the semiconductor device in which the contact hole is formed, a step of treating the semiconductor device with a cleaning liquid that dissolves the foreign matter, Since the semiconductor device to which the cleaning liquid adheres is treated with the rinse liquid having a viscosity of 5 cp or more and 40 cp or less, the diffusion speed of the cleaning liquid in the contact hole of the semiconductor device to the rinse liquid is determined by the bottom of the contact hole. It is possible to provide a cleaning method that can be controlled according to the foreign matter.

According to the sixth aspect of the present invention, since the rinse liquid of the cleaning method according to the fifth aspect is formed of 100% alcohol, a rinse liquid having a desired viscosity can be easily obtained. It is possible to provide a cleaning method that can be obtained.

According to the seventh aspect of the present invention, since the rinse liquid of the cleaning method according to the sixth aspect is formed of any one of ethylene glycol, phenol, ethanol and isopropyl alcohol, it is possible to surely obtain a desired liquid. It is possible to provide a cleaning method capable of obtaining a rinse liquid having a viscosity.

Further, according to claim 8 of the present invention, the viscosity of the rinse liquid in the cleaning method according to any one of claims 5 to 7 is controlled by the temperature of the rinse liquid. It is possible to provide a cleaning method that can be easily set to a rinse liquid having

According to a ninth aspect of the present invention, in the cleaning method according to any of the first to eighth aspects, the treatment with the rinse liquid is performed by rotating the semiconductor device. It is possible to provide a cleaning method capable of controlling the diffusion rate of the cleaning liquid into the rinse liquid by rotating the semiconductor device.

According to a tenth aspect of the present invention, in a cleaning device for removing foreign matters on the inner bottom of a contact hole of a semiconductor device having a contact hole formed therein, a coating device for coating the semiconductor device with the cleaning liquid and the cleaning liquid evaporating. It is possible to provide a cleaning device capable of evaporating the cleaning liquid in accordance with the elution of the foreign matter in the bottom portion of the contact hole of the semiconductor device into the cleaning liquid.

According to the eleventh aspect of the present invention, since the vaporizing means of the cleaning device according to the tenth aspect is constituted by the heating device and the depressurizing device, the cleaning liquid evaporation rate can be easily adjusted. A device can be provided.

According to a twelfth aspect of the present invention, in the cleaning apparatus according to the tenth aspect or the eleventh aspect, the rinse liquid is provided after the rinse liquid is provided with a rinse liquid applying means for applying the rinse liquid to the semiconductor device. Since it is applied to the semiconductor device, it is possible to provide a cleaning device capable of removing recrystallization of foreign substances eluted in the cleaning liquid.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a cleaning device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing steps of the cleaning method in the first embodiment of the present invention.

FIG. 3 is a diagram showing the relationship between the height of the contact hole and the concentration of the cleaning liquid in the contact hole of the semiconductor device according to the first embodiment of the present invention.

FIG. 4 is a diagram showing a configuration of a cleaning device according to a second embodiment of the present invention.

FIG. 5 is a diagram showing a configuration of a cleaning device according to a second embodiment of the present invention.

FIG. 6 is a diagram showing a configuration of a cleaning device according to a third embodiment of the present invention.

FIG. 7 is a diagram showing steps of a cleaning method in a third embodiment of the present invention.

FIG. 8 is a diagram showing a relationship between a height of a contact hole and an etching amount in a contact hole of a semiconductor device according to a third embodiment of the present invention.

FIG. 9 is a diagram showing a configuration of a conventional cleaning device.

FIG. 10 is a diagram for explaining foreign matter on the bottom inside the contact hole of the conventional semiconductor device.

FIG. 11 is a diagram illustrating a problem of a conventional cleaning method.

FIG. 12 is a diagram showing physical properties of temperature and viscosity of a substance.

[Explanation of symbols]

19,49,68 Cleaning solution, 20,44,44a, 44
b, 44c, 63 wafer, 25 first controller, 2
7,54 Rinse liquid, 32 Second controller, 38,38
a, 38b contact hole, 39 foreign matter, 45 driving device, 72 heating lamp.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshi Kanno 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Sanryo Electric Co., Ltd.

Claims (12)

[Claims] 1. A cleaning method for removing foreign matter from the bottom of the contact hole of a semiconductor device having a contact hole formed therein, wherein the semiconductor device has a viscosity of 5 cp or more and 40 cp or less and a cleaning liquid that dissolves the foreign matter. And a step of treating the semiconductor device having the cleaning liquid adhered thereto with a rinse liquid. 2. The cleaning method according to claim 1, wherein the cleaning liquid is formed from an organic or acid thickener, hydrogen fluoride or a hydrogen fluoride compound, and water. 3. The cleaning liquid thickening agent according to claim 2, wherein the thickening agent is an organic thickening agent of ethylene glycol, glycerin, cresol or phenol, or
A cleaning method characterized by forming with an acid-based thickener of phosphoric acid or sulfuric acid. 4. The cleaning method according to any one of claims 1 to 3, wherein the viscosity of the cleaning solution is controlled by the temperature of the cleaning solution. 5. A cleaning method for removing foreign matter on the inner bottom of the contact hole of a semiconductor device having a contact hole, the step of treating the semiconductor device with a cleaning solution that dissolves the foreign matter, and the step of depositing the cleaning solution. And a step of treating the above semiconductor device with a rinse liquid having a viscosity of 5 cp or more and 40 cp or less. 6. The rinse liquid of the cleaning method according to claim 5,
A cleaning method characterized by forming with 100% alcohols. 7. The rinse liquid of the cleaning method according to claim 6,
A cleaning method comprising forming with any of ethylene glycol, phenol, ethanol, and isopropyl alcohol. 8. The cleaning method according to any one of claims 5 to 7, wherein the viscosity of the rinse liquid is controlled by the temperature of the rinse liquid. 9. The cleaning method according to claim 1, wherein the treatment with the rinse liquid is performed by rotating the semiconductor device. 10. A cleaning device for removing foreign matter at the bottom of the contact hole of a semiconductor device having a contact hole, comprising: a coating device for coating a cleaning liquid on the semiconductor device; and a vaporizing device for evaporating the cleaning liquid. A cleaning device characterized by the above. 11. The cleaning device according to claim 10, wherein the vaporizing means of the cleaning device comprises a heating device and a pressure reducing device. 12. The cleaning apparatus according to claim 10 or 11, further comprising: a rinse liquid applying means for applying the rinse liquid to the semiconductor device, and applying the rinse liquid to the semiconductor device after evaporating the cleaning liquid. Cleaning device characterized by.