CN1873925A - Chemical Mechanical Polishing Method and Equipment for Avoiding Polishing Slurry Residue - Google Patents

Abstract

The invention provides a CMP device, wherein the device is provided with at least one spray hole arranged on the periphery of a base of the device, so that deionized water is sprayed to the spray hole of grinding slurry, and the spray hole is prevented from being blocked by the grinding slurry.

Description

Chemical Mechanical Polishing Method and Equipment for Avoiding Polishing Slurry Residue

technical field

The present invention provides a chemical mechanical polishing (CMP) method and equipment, in particular a chemical mechanical polishing method and equipment that prevents nozzle holes of a supplier from being blocked by crystallization of polishing slurry.

Background technique

With the development of small and dense components on a chip, the requirements for the depth of focus of lithography exposure are becoming more and more stringent. Because in VLSI (very large scale integration, VLSI) and ultra large scale integration (ultra large scale integration, ULSI) manufacturing processes, a large number of various components and multi-layer metal interconnection layers formed on semiconductor chips objects, will form a steep terrain (severe topography) on the semiconductor chip, which will cause difficulties in the subsequent deposition or pattern transfer (pattern transfer) manufacturing process. Therefore, before performing subsequent procedures, a planarization process must be performed on the chip surface.

The traditional planarization technology is mainly based on spin on glass (SOG) and resist etch back (REB) technology. However, SOG and REC cannot be used in the production process below 250 nanometers (nm). Perform global planarization. Therefore, chemical mechanical polishing (CMP) technology is mainly used for planarization in VLSI and ULSI manufacturing processes at present.

Generally speaking, CMP technology is to use appropriate grinding slurry and mechanical grinding to uniformly remove the target thin film layer (target thin film) with irregular surface on a semiconductor chip, so that the semiconductor chip can be processed after CMP. Can have a regular and planar surface. Among them, the grinding slurry is generally composed of chemical additives and grinding powders, and the chemical additives may be pH buffers, oxidants, or surfactants, etc., and the grinding powders may be silica or alumina. The surface of the wafer can be effectively planarized by the chemical reaction provided by the chemical additives and the mechanical grinding effect between the grinding powder and the wafer and the polishing pad.

The grinding slurry is generally composed of chemical additives and grinding powders, and the chemical additives may be pH buffers, oxidants or surfactants, etc., and the grinding powders may be silica, alumina or zirconia etc. The chemical reaction provided by the chemical additives and the mechanical grinding effect between the grinding powder and the chip and the polishing pad can effectively planarize the surface of the chip.

However, the slurry residues and chip surface debris removed by grinding will remain on the device components and chips to cause contamination. For example: residual particles may cause oxides to easily collapse, and polysilicon and metals may cause junction leakage or bridging, thereby reducing chip yield and reliability. Therefore, a cleaning procedure must be performed after the CMP process to avoid the above-mentioned pollution. The current traditional cleaning methods include wet chemical tank, ultrasonic (megasonic, ultrasonic, supersonic or finesonic) and brush scrubber (brush scrubber) cleaning. These cleaning procedures can remove the contaminants on the wafer and prevent the contaminants from causing surface defects on the chips.

However, these cleaning methods cannot remove the pollutants on the components of the grinding slurry supply, the grinding head and the like. For example, the nozzle hole of the abrasive slurry supplier may be blocked due to the crystallization of the abrasive slurry, and the crystallization may also fall on the chip to cause scratches on the chip. Therefore, effective methods are needed to solve the above problems.

Contents of the invention

Therefore, the main purpose of the present invention is to provide a CMP method to improve the problem of residual pollutants on CMP device components in the traditional CMP manufacturing process.

Another object of the present invention is to provide a CMP device for performing the above CMP method.

According to the present invention, a CMP device is provided, which includes a base having a central area and a peripheral area, wherein a platform is provided in the central area, a polishing pad is placed on the platform, and at least one nozzle. In addition, the device also includes a supplier arranged above the grinding pad, the supplier has at least one spray hole, and can be used to spray grinding slurry or deionized water on the grinding pad. The device is used to carry out a grinding process. In the process, a chip is carried by a chip carrier, and the chip is brought into contact with the grinding pad. And after the grinding process is completed, a rinsing process is carried out, using the supplier to spray deionized water on the polishing pad through the spray hole, and at the same time using the nozzle on the peripheral area to spray deionized water to the supply The spray hole on the device is used to prevent the abrasive slurry crystallization from blocking the spray hole.

The CMP method and device provided by the present invention can effectively remove the grinding slurry or other pollutants remaining on the nozzle hole of the supplier and other components, prevent the plugging of the nozzle hole and prevent these pollutants from causing chips in the subsequent manufacturing process. scratches.

Description of drawings

FIG. 1 is a schematic diagram of a chemical polishing device according to a specific embodiment of the present invention.

Explanation of main component symbols

210 CMP device 222 platform

212 chip 230 supplier

214 Carrier 231 Nozzle

216 Base 232 Nozzle

218 Axis A central area

220 Abrasive pad B Peripheral area

Detailed ways

Compared with the traditional CMP method and device, the CMP method and device of the present invention can clean the components of the device such as the abrasive slurry supplier in each rinsing procedure, thereby effectively preventing the residual pollutants on these components from affecting the subsequent The quality of the CMP fabrication process.

Please refer to FIG. 1 , which shows a schematic structural diagram of a preferred embodiment of the CMP apparatus of the present invention. As shown in FIG. 1 , the CMP apparatus 210 of the present invention includes a base 216 with a platform 222 on the base 216 . Taking the edge of the platform 222 as a boundary, the base 216 can be divided into two parts, a central area A and a peripheral area B. In the central area A of the base, there is a grinding pad 220 on the platform 222; particularly, in the peripheral area B of the base 216 of the present invention, a plurality of nozzles 232 with adjustable spraying angles are provided to deionized water. spray. Above the polishing pad 220 is a rotatable chip carrier 214 for carrying the chip 212 and a supplier 230 for providing polishing slurry or deionized water. The supplier 230 includes a grinding slurry pipeline and a deionized water pipeline (not shown), and has at least one spray hole 231 for supplying grinding slurry or deionized water from the spray hole respectively.

In addition, the center of the platform 222 has a shaft 218 connected to the base of the grinding device, and the shaft 218 is driven by a motor (not shown) in the base to rotate the platform 222 and the grinding pad 220 .

According to a preferred embodiment of the method of the present invention, the chip 212 is carried by the chip carrier 214 so as to be in contact with the polishing pad 220 . Then, the polishing slurry is provided to the polishing pad 220 by the supplier 230 having the spray hole 231 , and the chip 212 and the polishing pad 220 are relatively moved. For example, the shaft 218 driven by the motor rotates the platform 222 clockwise, and the carrier 214 carrying the chips 212 rotates counterclockwise. Meanwhile, a polishing slurry, such as colloidal silicon suspended in an aqueous potassium hydroxide solution, is provided on the polishing pad 220 by the polishing slurry supplier 230 to facilitate polishing of the chip 212 . After the grinding process is finished, a rinsing process is performed.

In this rinsing process, the supplier 230 provides deionized water on the chip 212, and the nozzles 232 provide deionized water to the supply nozzles 231, wherein the angle of the nozzles 232 can be adjusted so that deionized The ionized water is sprayed toward the nozzle hole 231 at an appropriate angle. In addition, since the deionized water line of the supplier 230 and the deionized water line (not shown) of the nozzle 232 are connected to the same deionized water source, both can be turned on and spray water at the same time.

In another embodiment of the present invention, the nozzles 232 are nozzles with fixed angles, except that the nozzles 232 spray water to the spray holes 231 at a predetermined angle. The predetermined angle refers to the angle formed by the nozzle 232 and the spray hole 231 under the condition that the deionized water sprayed by the nozzle 232 can wash the spray hole 231 .

Compared with the conventional technology, the present invention provides at least one nozzle 232 on the CMP device 210 in particular, and this nozzle 232 can carry out the cleaning of the abrasive slurry supplier 230 and the upper spray hole 231 thereof in the same rinsing manufacturing process, therefore, there is no need to The additional cleaning step can clean the residual grinding slurry crystals, so as to prevent these residues from affecting the quality of the subsequent manufacturing process. In addition, since the nozzle 232 is located in the existing surrounding space (peripheral area B) of the device 210, that is, the existing machine can be directly installed, which is easy to implement and apply.

The above descriptions are only preferred embodiments of the present invention, and all equivalent changes and modifications made according to the present invention shall fall within the scope of the present invention.

Claims (10)

1. chemical and mechanical grinding method, this method may further comprise the steps at least:

One chemical mechanical polishing device is provided, and it comprises that one has the base of a middle section and a neighboring area, wherein is provided with a platform in this middle section, is equipped with a grinding pad on this platform, and is provided with at least one nozzle in this neighboring area; This device comprises that also one is located at a supply of this grinding pad top, has at least one spray orifice on this supply and is used for ground slurry or deionized water are sprayed at this grinding pad;

Carry out one and grind manufacture craft, wherein utilize a chip carrier to carry a chip, and this chip is contacted with this grinding pad; And

After finishing this grinding manufacture craft, carry out a rinse manufacture craft, utilize this supply that deionized water is sprayed on the grinding pad via this spray orifice, utilize this nozzle on this neighboring area that deionized water is sprayed to this spray orifice on this supply simultaneously, stop up this spray orifice to avoid the ground slurry crystallization.

2. method according to claim 1, there is an axle that is connected to this lapping device base in wherein above-mentioned platform central authorities, and this system is by the motor driven in this base, thereby rotate this platform and this grinding pad.

3. method according to claim 1 includes first di water line that a ground slurry pipeline and is connected to a deionized water source of supply in the wherein above-mentioned supply.

4. method according to claim 1, wherein above-mentioned nozzle is connected to this deionized water source of supply by one second di water line.

5. method according to claim 1, wherein above-mentioned nozzle adjustable angle.

6. chemical mechanical polishing device, this device comprises following assembly at least:

One has the base of a middle section and a neighboring area, wherein is provided with a platform at this middle section, is equipped with a grinding pad on this platform, and is provided with at least one nozzle in this neighboring area;

One is located at a supply of this grinding pad top, has at least one spray orifice on this supply and is used for ground slurry or deionized water are sprayed at this grinding pad; And

One chip carrier to be carrying a chip, and this chip is contacted with this grinding pad;

Wherein this nozzle is in a rinse manufacture craft, and deionized water is sprayed to this spray orifice on this supply, stops up this spray orifice to avoid the ground slurry crystallization.

7. device according to claim 6, there is an axle that is connected to this lapping device base in wherein above-mentioned platform central authorities, and this axle is by the motor driven in this base, thereby rotate this platform and this grinding pad.

8. device according to claim 6 includes first di water line that a ground slurry pipeline and is connected to a deionized water source of supply in the wherein above-mentioned supply.

9. device according to claim 6, wherein above-mentioned nozzle is connected to this deionized water source of supply by one second di water line.

10. method according to claim 6, this wherein above-mentioned nozzle adjustable angle.