Patent Application
20160346901
This application is based upon and claims priority under 35 U.S.C. 119(a) from Taiwan Patent Application No. 104117686 filed on Jun. 1, 2015, which is hereby specifically incorporated herein by this reference thereto.
The present invention relates to a chemical mechanical polishing field and more particularly to a chemical mechanical polishing (CMP) conditioner.
CMP, being a large area planarization technique, is an important method for semiconductor manufacturing. Users can prepare a pad on the platform, and further add slurry on the surface of the pad. The pad can be rotated with the platform. The rotating direction of the pad is relative to a wafer, and the surface of the wafer is polished by the pad. It is beneficial to advance subsequent processes after planarization of the wafer. The efficiency of polishing may be preserved by maintaining the roughness of the pad. A hardened layer is formed gradually on the surface of the pad by accumulating the slurry and the scraps produced by wafer during the polishing process. The hardened layer decreases the polishing efficiency and shortens the lifetime of the pad.
In order to maintain the roughness of the pad, users need a CMP conditioner to dress the surface of the pad continuously during the polishing process, so as to prolong the life time of the pad. With enlargement of the wafer size in the semiconductor manufacturing, the influences of wafer quality become more obviously from difference between the center of the wafer and the outer edge of the wafer. The requirements of diverse polishing capabilities for different regions of CMP conditioner increase gradually from the current industry. Similarly, the CMP conditioner needs to have diverse polishing capabilities for different regions.
In view of the abovementioned problem, Taiwan Patent Application No. 97110627 discloses a cutting tool for ultra hard material comprising: a base, a plurality of cutting units, and a combining unit. The base is a disc. A through hole is formed in the center of the base. A working surface is formed on one side of the base. There are multiple long troughs disposed on the working surface. The cutting units have cutting ends. Multiple sharp peaks are formed on the cutting ends. The multiple sharp peaks are parallel with one another. Each cutting unit has two sides. The first side is mounted in the long troughs, and the second side is mounted out of the long troughs. The cutting ends protrude from the working surface. The combining unit is binding with the cutting units on the base. This patent utilizes the long troughs to change the inclined angle of the cutting tool and then increases the cutting efficiency. However only the cutting ends of the cutting tool protrude from the working surface, and the cutting ends are really smaller than the whole cutting unit. In order to change the cutting capability for each region, users need to regulate the height of each cutting end protruding from the working surface separately to achieve continuously different dressing depths. The processes are very complicated and time consuming. It is not good for mass production.
Patent publication TW 201029805A1 discloses an apparatus for dressing a polishing pad comprising: a dresser drive shaft which is rotatable and vertically movable, a dresser flange coupled to the dresser drive shaft and configured to secure a dressing member thereto, a spherical bearing provided in the dresser flange and configured to allow the dressing member to tilt with respect to the dresser drive shaft, and a spring mechanism configured to generate a force against a tilting motion of the dressing member. This patent utilizes the spherical bearing to help the dressing member to be oblique to the dresser drive shaft. The vibration vertical to the polishing pad of the apparatus from the polishing process can be relieved, then decreasing the loading of the apparatus. The problem of this patent is that the inclined angle between the polishing pad and the dressing member cannot be regulated partially during the polishing process.
Taiwan Patent Application No. 96125259 discloses an apparatus for conditioning a conductive polishing material. The apparatus comprises a backing plane and an annular member. The backing plane is adapted to couple to a conditioning head assembly. The backing plane comprises a rigid disk. The rigid disk has a first side and an opposing second side. The second side has a perpendicular orientation to a centerline of the backing plate. The annular member has a base portion adhered to the second side of the backing plate. The annular member defines a conditioning surface opposite the second side that is radially sloped relative to a plane of the second side. This patent utilizes the above radial oblique to form an inclined plane. In order to construct different heights of the polishing surface, the annular member should be working repeatedly. The problem of this patent is that working complication and high accuracy of processing are hard to control.
Therefore, the conventional CMP conditioner still needs to be improved to meet the requirement in the industry.
An objective of the present invention is to provide a CMP conditioner having diverse polishing capabilities on different regions. The present invention of the above CMP conditioner can meet the requirements in the industry.
The present invention provides a CMP conditioner comprising:
a substrate comprising a horizontal top surface; and
multiple abrasive units respectively mounted on the horizontal top surface; each of the multiple abrasive units comprising: a base of the abrasive unit, an abrasive layer, and a binding layer; the base of the abrasive unit comprising an upper surface and a lower surface, and the upper surface being opposite the lower surface; the abrasive layer formed on the upper surface and comprising multiple abrasive tips; the binding layer formed between the lower surface and the substrate, and an inclined plane formed towards the lower surface.
The polishing capabilities of different regions of the CMP conditioner in the present invention can be regulated by abrasive units of the horizontal top surface. Each base of the abrasive unit is oblique to the horizontal top surface of the substrate by the inclined plane of the binding layer. The continuously different dressing depths of the abrasive tips may be formed to control the polishing capability for each abrasive unit when dressing the surface of the polishing pad. The CMP conditioner of the present invention satisfies diverse requirements of polishing capabilities in the current industry.
Preferably, each of the multiple abrasive units further comprises a mat. The mat is mounted between the horizontal top surface of the substrate and a side of the lower surface. The binding layer is formed among the lower surface, the mat, and the horizontal top surface. The inclined plane is formed toward the lower surface.
In addition, the substrate further comprises multiple concave portions. The multiple concave portions are recessed into the horizontal top surface of the substrate. Each of the multiple concave portions comprises a bottom surface. Each of the multiple abrasive units further comprises a mat. The mat is mounted between the bottom surface of the concave portion and a side of the lower surface. The binding layer is formed among the lower surface, the mat, and the bottom surface.
Furthermore, the substrate further comprises multiple concave portions. The multiple concave portions are formed through the substrate. The CMP conditioner further comprises a base plate, and the base plate comprises a surface of the base plate. The surface of the base plate is attached on the substrate and opposite the horizontal top surface. Each of the multiple abrasive units further comprises a mat. The mat is mounted among the concave portion, the surface of the base plate, and a side of the lower surface. The binding layer is formed between the lower surface and the surface of the base plate. The concave portions provide better fixing effects for the abrasive units. In addition, the distance between the abrasive tip and the horizontal top surface can be controlled by changing the depth of each of the concave portions.
Preferably, a height of the abrasive tip on one side is higher than a height of the abrasive tip on the other side. The difference between the heights of the abrasive tips on one side and the other side is larger than or equal to 3 μm and less than or equal to 50 μm.
Preferably, the substrate comprises a central axis. A normal direction of the horizontal top surface is parallel to the central axis, and the central axis is on the center of the horizontal top surface. The inclined plane faces toward the central axis of the substrate.
In addition, the inclined plane faces away from the central axis of the substrate.
Additionally, the inclined planes of the binding layers for a part of the multiple abrasive units face toward the central axis of the substrate. The inclined planes of the binding layers for another part of the multiple abrasive units face away from the central axis of the substrate.
Furthermore, the inclined plane faces toward a mat of the adjacent abrasive unit tandemly.
Preferably, the substrate is a stainless steel substrate, a die steel substrate, a metal alloy substrate, a ceramic substrate, a plastic substrate, or a combination thereof.
Preferably, the thickness of the substrate is larger than or equal to 4 mm and less than or equal to 30 mm.
Preferably, materials of the binding layer comprise ceramic materials, brazing materials, plating materials, or polymer materials. More preferably, the brazing materials comprise: iron, cobalt, chromium, manganese, silicon, aluminum, or combinations thereof. The polymer materials comprise: epoxy, polyester resins, polyacrylic acid resins, or phenol formaldehyde resins.
Preferably, the base of the abrasive unit is a conductive base or an insulated base. More preferably, the conductive base comprises: molybdenum, tungsten, or tungsten carbide.
Preferably, the insulated base comprises ceramic materials. More preferably, the ceramic materials comprise silicon carbide. The single crystal materials comprise silicon or aluminium oxide.
Preferably, the insulated base comprises single crystal materials. More preferably, the single crystal materials comprise silicon, aluminium oxide, or sapphire.
Preferably, an abrasive membrane is formed on the abrasive layer. The abrasive membrane comprises a ceramic film or diamond film. The ceramic film comprises: aluminium oxide, zirconia, silicon carbide, titanium nitride, or aluminium-titanium oxide. The diamond film comprises: single crystal diamond or polycrystalline diamond.
Preferably, the shortest vertical distance between the top of the abrasive tip and the lower surface is larger than or equal to 2 mm and less than or equal to 10 mm. More preferably, the shortest vertical distance between the top of the abrasive tip and the lower surface is larger than or equal to 4 mm and less than or equal to 6 mm. The most preferably, the shortest vertical distance between the top of the abrasive tip and the lower surface is 4 mm.
Preferably, a shape of the abrasive tip is blade-shaped, conical, arced, cylindrical, pyramidal, or prismatic. More preferably, the prismatic shape is rectangular prism.
Preferably, the tip angle of the abrasive tip is larger than or equal to 60° and less than or equal to 120°. More preferably, the tip angle of the abrasive tip is 60°, 90°, or 120°.
Preferably, a thickness of the mat is larger than or equal to 3 μm and less than or equal to 50 μm.
Preferably, materials of the mat comprise stainless steel or plastic.
The present invention further provides a CMP conditioner comprising:
providing multiple abrasive units;
providing a substrate comprising a horizontal top surface;
mounting multiple mats on the horizontal top surface;
abutting a side of each abrasive unit against the multiple mats respectively, and each abrasive unit contacting the horizontal top surface obliquely; and
forming a binding layer between each abrasive unit and the horizontal top surface, then obtaining the CMP conditioner.
Preferably, the step of providing multiple abrasive units comprises:
providing multiple bases of the abrasive units; each base of the abrasive units comprising an upper surface and a lower surface, and the upper surface being opposite the lower surface; and
forming an abrasive layer on the upper surface to obtain the abrasive units, and the abrasive layer comprising multiple abrasive tips.
Preferably, the steps of abutting a side of each abrasive unit against the multiple mats and forming a binding layer comprise:
abutting one side of the lower surface against the multiple mats respectively, and the other side of the lower surface contacting the horizontal top surface; then each abrasive unit contacting the horizontal top surface obliquely; and
forming a binding layer between the lower surface and the horizontal top surface to obtain the CMP conditioner.
In addition, the step of abutting a side of each abrasive unit against the multiple mats comprises:
providing a flat jig comprising a jig surface;
mounting multiple mats on the jig surface;
abutting one side of the abrasive layer against the multiple mats respectively, and the other side of the abrasive layer contacting the jig surface;
mounting the substrate on the lower surface of each abrasive unit horizontally, then each abrasive unit contacting the horizontal top surface obliquely; and
wherein the step of forming a binding layer comprises:
forming the binding layer between the lower surface and the horizontal top surface, then removing the flat jig and the multiple mats; obtaining the CMP conditioner finally.
Preferably, the vertical distance between the lower surface and the horizontal top surface is larger than or equal to 3 μm and less than or equal to 50 μm.
Preferably, each of the inclined planes faces toward the central axis of the substrate.
In addition, each of the inclined planes faces away from the central axis of the substrate.
Additionally, the inclined planes of the binding layers for a part of the multiple abrasive units face toward the central axis of the substrate. The inclined planes of the binding layers for another part of the multiple abrasive units face away from the central axis of the substrate.
Preferably, the substrate is a stainless steel substrate, a die steel substrate, a metal alloy substrate, a ceramic substrate, a plastic substrate, or a combination thereof.
Preferably, the thickness of the substrate is larger than or equal to 4 mm and less than or equal to 30 mm.
Preferably, materials of the binding layer comprise ceramic materials, brazing materials, plating materials, or polymer materials. More preferably, the brazing materials comprise: iron, cobalt, chromium, manganese, silicon, aluminum, or combinations thereof. The polymer materials comprise: epoxy, polyester resins, polyacrylic acid resins, or phenol formaldehyde resins.
Preferably, the base of the abrasive unit is a conductive base or an insulated base. More preferably, the conductive base comprises: molybdenum, tungsten, or tungsten carbide.
Preferably, the insulated base comprises ceramic materials. More preferably, the ceramic materials comprise silicon carbide. The single crystal materials comprise silicon or aluminium oxide.
Preferably, the insulated base comprises single crystal materials. More preferably, the single crystal materials comprise silicon or aluminium oxide.
Preferably, the shortest vertical distance between the top of the abrasive tip and the lower surface is larger than or equal to 2 mm and less than or equal to 10 mm. More preferably, the shortest vertical distance between the top of the abrasive tip and the lower surface is larger than or equal to 4 mm and less than or equal to 6 mm. The most preferably, the shortest vertical distance between the top of the abrasive tip and the lower surface is 4 mm.
Preferably, a shape of the abrasive tip is blade-shaped, conical, arced, cylindrical, pyramidal, or prismatic. More preferably, the prismatic shape is rectangular prism.
Preferably, the tip angle of the abrasive tip is larger than or equal to 60° and less than or equal to 120°. More preferably, the tip angle of the abrasive tip is 60 °, 90°, or 120°.
Preferably, a thickness of the mat is larger than or equal to 3 μm and less than or equal to 50 μm.
Preferably, materials of the mat comprise stainless steel or plastic.
The method for manufacturing a CMP conditioner of the present invention is good for speedy and large-scaled mass production. The polishing capability of different regions of CMP conditioner can be regulated by the base of the abrasive units and the abrasive tips. The continuously different dressing depths are formed on the abrasive tips by the different arrangements of the binding layer. The present invention of the above CMP conditioner can meet the requirements in the current industry.
With reference to
The lower surface comprises an abutting side 211 and a mating side 212. The abutting side 211 is opposite the mating side 212. The abutting side 211 is abutting against the horizontal top surface 11, and the mating side 212 is in contact with the mat 23. A height of the abrasive tips 221 on the mating side 212 is higher than the height of the other abrasive tips 221 on the abutting side 211. The height difference d2 between the abrasive tips 221 on the mating side 212 and the other abrasive tips 221 on the abutting side 211 is 10 μm.
The mat 23 is a sheet. The mat 23 is made of stainless steel. The mat 23 is attached on the horizontal top surface 11. In particular, the mat 23 is mounted on the mating side 212 of the base 21 of the abrasive unit. The thickness of the mat 23 is 10 μm.
The binding layer 24 is filled among the lower surface, the horizontal top surface 11, and the mat 23. The binding layer 24 comprises an inclined plane 241. The inclined plane 241 is formed on the lower surface and faces to the central axis. The binding layer 24 is made of iron.
The polishing capability of each region for the CMP conditioner 1 can be regulated by the abrasive units 20 on the horizontal top surface 11. Each base 21 of the abrasive unit is oblique to the horizontal top surface 11 by the mat 23 and the binding layer 24.The slope of the inclined plane 241 can be regulated by arrangement of the mat 23 and the binding layer 24. The continuously different dressing depths are formed on the abrasive tips 221 by the above arrangement in the polishing process. Users can further change the polishing capability for each abrasive unit 20.
With reference to
The number of the abrasive units 20A is three. The base 21A of the abrasive unit is arc-shaped. The base 21A of the abrasive unit is an insulated base. The base 21A of the abrasive unit is made of silicon carbide. The base 21A of the abrasive unit comprises a smooth surface. The abrasive layer 22A is deposited on the smooth surface by CVD. Multiple abrasive tips 221A are formed through the above method. The shortest vertical distances d1 between a tip of each abrasive tip 221A and the lower surface is 5 mm. The height difference d2 between the abrasive tips 221A on the mating side 212A and the abrasive tips 221A on the abutting side 211A is 20 μm.
The mat 23A is made of plastic, and the thickness of the mat 23A is 20 μm.
The binding layer 24A is made of epoxy. The inclined plane 241A faces away from the central axis of the substrate 10A.
The second embodiment of the present invention provides a CMP conditioner 1A that utilizes changing the shape of the base 21A of the abrasive unit and the direction of the inclined plane 241A for the binding layer 24A to achieve different polishing capabilities from the CMP conditioner 1 of the first embodiment of the present invention.
With reference to
The third embodiment of the present invention provides a CMP conditioner 1B that utilizes changing shapes of the abrasive tips 221B and the direction of the inclined plane 241B for the binding layer 24B to achieve different polishing capabilities from CMP conditioner 1 of the first embodiment of the present invention.
The polishing capabilities of each region of the CMP conditioner can be regulated by changing the arrangement and the position of the abrasive units, changing the shapes of the base 21B of the abrasive units, changing the longest vertical distance between the lower surface and the horizontal top surface (slope), changing the shapes of the abrasive tips, or changing the direction of the inclined plane of the binding layer for the CMP conditioner of the present invention. The CMP conditioner of the present invention can meet the requirement in the industry.
The present invention further provides a method for manufacturing a CMP conditioner comprising the following steps:
Firstly, prepare a substrate which comprises a horizontal top surface. Then the multiple mats are attached on the horizontal top surface of the substrate.
Prepare multiple bases of the abrasive unit and each base of the abrasive unit comprises an upper surface and a lower surface. The number of the bases of the abrasive units is equal to the number of the mats.
An abrasive layer is deposited on the upper surface by CVD. The abrasive layer comprises multiple abrasive tips. The material of the abrasive layer comprises polycrystalline diamond.
The lower surface comprises two opposite sides. One side is an abutting side, and the other side is a mating side. The mating side is in contact with the mat, and the abutting side is abutting against the horizontal top surface.
In order to obtain the CMP conditioner, fill a binding layer among the mat, the lower surface, and the horizontal top surface. An inclined plane of the binding layer is formed on the lower surface. The binding layer is made of epoxy. The method for manufacturing a CMP conditioner of the present invention is very simple. It is good for speedy and large-scale mass production. The polishing capability of different regions of CMP conditioner can be regulated by the base of the abrasive units and the abrasive tips. The continuously different dressing depths are formed on the abrasive tips by the different arrangements of the binding layer and the mat. The present invention of the above CMP conditioner can meet the requirements in the current industry.
With reference to
When the CMP conditioner 1C is used for dressing the surface of the polishing pad, the directions of the inclined planes are the same with the rotating direction of the CMP conditioner 1C. The resistance between the CMP conditioner 1C and the polishing pad can be reduced, so as to prolong the life time of the CMP conditioner 1C indirectly.
With reference to
The fifth embodiment of the present invention provides better fixing effects for the abrasive units 20D through the multiple concave portions 12D.
With reference to
The sixth embodiment of the present invention provides better fixing effects for the abrasive units 20E through the multiple concave portions 12E.
With reference to
With reference to
First of all, prepare a flat jig 50F which comprises a jig surface 51F. Then the multiple mats 23F are attached on the jig surface 51F.
Prepare multiple bases 21F of the abrasive unit, each base 21F of the abrasive unit comprising an upper surface and a lower surface. The number of the bases 21F of the abrasive unit is equal to the number of the mats 23F.
The abrasive layer 22F is deposited on the upper surface by CVD. The abrasive layer 22F comprises multiple abrasive tips 221F. The material of the abrasive layer 22F comprises polycrystalline diamond.
One side of the abrasive layer 22F abuts against the mat 23F, and the other side of the abrasive layer 22F abuts against the jig surface 51F. The lower surface is oblique.
Then prepare the substrate 10F which comprises a horizontal top surface 11F. The horizontal top surface 11F abuts a side of the lower surface. The substrate 10F is parallel to the flat jig 50F.
In order to obtain the CMP conditioner 1F, remove the flat jig 50F and the mats 23F after filling the binding layer 24F between the substrate 10F and the lower surface. The inclined plane 241F of the binding layer 24F is formed on the lower surface. The binding layer 24F is made of epoxy.
The method for manufacturing a CMP conditioner of the present invention is very simple. It is good for speedy and large-scale production. The polishing capabilities of different regions of CMP conditioner can be regulated by the base of the abrasive units and the abrasive tips. The continuously different dressing depths are formed on the abrasive tips by the different arrangements of the binding layer. The above CMP conditioner of the present invention can meet the requirements in the current industry.
| Number | Date | Country | Kind |
|---|---|---|---|
| 104117686 | Jun 2015 | TW | national |
