TWI303406B - Diamond conditioning of soft chemical mechanical planarization/polishing (cmp) polishing pads - Google Patents

Description

(1) 1303406 IX. Description of the Invention [Technical Fields of the Invention] Embodiments of the present invention relate to chemical mechanical planarization/polishing (CMP), particularly to the finishing of CMP polishing pads. [Prior Art] Chemical mechanical planarization/polishing (CMP) was developed in the mid-1980s as a method of producing integrated circuits on substrates or wafers. The CMP method is used to fabricate wafers or to fabricate semiconductor devices or structures on wafers. A CMP method can be used to planarize (and even flat) a semiconductor layer on a wafer, planarize an insulating layer on the semiconductor layer, and planarize a conductive layer on the insulating layer into a predetermined pattern. A typical CMP system includes a wafer carrier and a roller assembled in a housing. A polishing pad is attached to the roller and the wafer to be polished is fixed to the wafer carrier. A typical CMP process operates as follows: a wafer carrier spins the wafer and/or a roller to rotate the polishing pad, applies a chemical slurry to the surface of the polishing pad, and contacts and polishes (or planarizes) the wafer and the polishing pad. The use of chemical slurry in combination with mechanical rotation produces the term 'chemical- mechanical planarization'. When the wafer is polished, the chemical paste and the material removed from the wafer have a tendency to smooth the surface of the polishing pad. This makes the polishing pad slippery and reduces polishing rate and efficiency. Therefore, it is important to keep the surface of the polishing pad clean and free from jaggedness. The method of cleaning the polishing pad is sometimes referred to as 'conditioning or refreshing' 〇 (4) .1303406 water to the surface of the soft polishing pad 108, and the trimming arm 110 sweeps over (e.g., returns) the soft polishing pad 108. While in some embodiments, the soft bake pad 108 may be trimmed non-locally (between polishing of each wafer 106), in other embodiments, (when the wafer 106 is being polished) soft buffing Pad 108 performs trimming in place, or in another embodiment, combines two polishing profiles. Of course, in accordance with an embodiment of the present invention, the soft polishing pad 108 can be trimmed prior to polishing the wafer 106. # One or a combination of the following method parameters can be modified to improve the method of trimming the soft buff pad 108 using the diamond trimmer 112 to ensure that the trim arm 110 with the diamond trimmer 112 does not damage or severely reduce the soft bake pad 108. Life. Life. In fact, the life of the soft polishing pad 108 of the embodiment of the present invention is significantly improved. Increasing the life of the soft pad 108 reduces labor costs and parts costs and improves procedures (e.g., without having to replace the soft pad 108 frequently). In one embodiment, the trim arm 110 applies 0.25 psi to the soft polishing pad 108 via the diamond trimmer 112. In contrast, the conventional technique _ using a hard polishing pad requires about 3 p s i. In conventional soft pad conditioning techniques, the rollers and soft polishing pads do not rotate. In the embodiment of the present invention, the rotational speed of the drum 104 and the soft polishing pad 1 8 may be about 1 revolution per minute (rpm). In conventional soft pad conditioning methods, no deionized water can flow to the soft pad. In an embodiment of the invention, the volumetric flow rate of deionized water from the deionized water tank 116 may be 1 plus gpm per minute, or any deuterium from about 1 gallon per minute. In the conventional soft polishing pad dressing method, the diamond dresser is not used, because -8 - (5) 1303406 does not apply downward force to the soft polishing pad. In one embodiment, the downward force applied by the diamond trimmer 112 to the soft polishing pad can be 0.25 psi. In the conventional soft polishing pad finishing method, a diamond dresser is not used. In the conventional hard polishing pad dressing method, the diamond dresser is swept at least 10 times. In one embodiment, the diamond trimmer 112 sweeps through the soft polishing pad only once. The third figure illustrates an example of a polishing pad 108 in accordance with an embodiment of the present invention. The illustrated polishing pad 108 includes a plurality of apertures 322 and may be formed from a polyester film or a fuzzed porous urethane layer on a compressible carbamic acid #ethyl ester substrate. In another embodiment, the exemplified soft polishing pad 108 can be formed from a cushion made of entangled polymer fibers coated with polyurethane. In still another embodiment, the soft polishing pad 1 8 of the illustration may be a fibrous felt sheet rich in fine pore elastomer. In still another embodiment, the exemplified soft buff pad 108 can be a porous thermoplastic resin matrix (typically polyurethane) reinforced with a fiber web reinforced with, for example, a polymer fiber felt pad. Examples of suitable cushions include any of the Politex® series of polishing pads available from Rodel Holdings in Wilmington, Delaware. The soft polishing pad 108 of the embodiment of the present invention differs from conventional hard polishing pads. The hard polishing pad comprises a fine porous polyurethane polishing pad which is relatively hard and less compressible than other types of polishing pads and polyurethane-rich felt polishing pads. Examples of hard pads include the SUB A 1000 Series polishing pads and SUBA®, available from Rodel, Phoenix, Arizona. The fourth figure illustrates the operation of the trimming arm 110 in accordance with an embodiment of the present invention. When the soft pad 108 is moved to polish the wafer 106, the trim arm 110 (and diamond trim 112) remains in position 402 near the circumference of the soft bake pad 108. After the soft polishing (6) J303406 optical pad 108 is polished a predetermined number of wafers, or the polishing rate is lowered due to the generation of slurry and debris, one end of the conditioning arm 110 is pivoted by the pedestal 107 and lowered to soft polishing. The pad 108 is then swept from the position 402 across the surface of the pad 108 (shown in phantom) along the arc shown by arrow 408 to the vicinity of the other side of the soft pad 108 (also shown as a dashed line). The fifth figure illustrates a diamond dresser 112 in accordance with an embodiment of the present invention. The diamond trimmer 11 2 includes a bottom 502 having a diamond 504. The bottom 50 2 can be any suitable rigid substrate of 0. Diamond 504 can be a synthetic diamond, a natural diamond, or the like. Diamond 504 can be placed on bottom 502 by chemical vapor deposition (CVD). Diamond 504 in another embodiment can be embedded in bottom 502. For example, the diamond dresser 112 can be formed by embedding diamond particles in a conventional or proprietary technique on nickel applied to the surface of a rigid substrate. • Embodiments of the invention may be implemented using a combination of hardware, software, firmware, or a combination of hardware and soft body. When implemented in software, the software can be stored in a computer program product (such as a compact disc, a magnetic disk, a floppy disk, etc.), or a program storage device (such as a CD player, a disk drive, a floppy disk drive, etc.). The above description of the illustrated embodiments of the present invention is not intended to be exhaustive or limited to the precise forms disclosed. While the invention has been described herein with respect to the specific embodiments or examples, various modifications may be possible within the scope of the invention. These modifications can be obtained from the present invention in accordance with the above description. In the above description, numerous specific details are set forth, such as specific procedures, materials, devices, etc., in order to provide a full understanding of the embodiments of the invention. 10- (7) 1303406 Method or component, etc., can still be implemented. In other instances, well-known constructions or operations have not been shown or described in detail to avoid obscuring and affecting the description. Various operations are illustrated in a manner in which multiple operations are performed in a separate manner to assist in understanding embodiments of the present invention. However, the order of the description does not constitute that the operation is required to be in this order, and it is not intended that the operations proposed by the present invention are to be performed in this order. • The description refers to 'an embodiment' or 'an embodiment', meaning The particular shapes, configurations, procedures, blocks, and features described in the embodiments are included in at least one embodiment of the invention. Therefore, the appearance of the <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; Furthermore, the particular shapes, configurations, features of an embodiment or more may be combined in a suitable manner. The words used in the following claims are not intended to limit the invention to the specific embodiments disclosed herein. On the contrary, the scope of the embodiments of the present invention is fully determined by the scope of the following claims, which are interpreted in accordance with the principles of the claims. BRIEF DESCRIPTION OF THE DRAWINGS In the drawings, like reference numerals generally indicate the same, functionally similar, and/or structurally equivalent elements. The first occurrence of the symbol is indicated by the leftmost digit of the reference number. Wherein: Figure 1 is a schematic illustration of one embodiment of a chemical mechanical planarization (CMP)/polishing system of the present invention; -11-(8) 1303406 Figure 2 is an embodiment of a chemical mechanical planarization (CMP) polishing system of the present invention A flowchart of the method performed; FIG. 3 illustrates an example of a soft polishing pad according to an embodiment of the present invention; FIG. 4 illustrates an operation of a trimming arm of an embodiment of the present invention; and FIG. 5 illustrates a diamond dresser of an embodiment of the present invention.

[Illustration] 100 Chemical mechanical planarization polishing system 101 Housing 102 Polishing head 103 Control panel 104 Roller 105 Spindle 106 Wafer 107 Base 108 Soft polishing pad 112 Diamond dresser 114 Slurry tank 116 Sink 118 Electromechanical equipment 120 Arrow 122 Arrow 200 Method 302 Hole-12- 1303406 Ο) 402 Position 406 Second Position 408 Arrow 502 Bottom 504 Diamond

Claims (1)

1303406 (1) X. Application for Patent Scope Annex 2: Patent Application No. 95 1 1 3436 Application for Patent Application Replacement of the Republic of China on March 5, 1997 Revision 1 · A method for dressing a chemical mechanical planarization (CMP) polishing pad , comprising: a soft polishing pad rotating on a drum, wherein the soft polishing pad comprises a raised venting porous urethane selected from a polyester film, a raised permeable porous urethane on a compressible urethane substrate, and a urethane-coated entangled polymer fiber a fiber felt sheet enriched in a fine pore elastomer, or a polishing pad of at least one of a porous thermoplastic resin matrix reinforced with a fiber web; ^ cleaning the soft polishing pad; and passing a diamond dresser Above the soft polishing pad. 2. The method of trimming the chemical mechanical planarization φ polishing pad as described in claim 1, further comprising: the roller has no force on the soft polishing pad. 3. A method of trimming the chemical mechanical planarization polishing pad as described in claim 1, wherein the trimming arm having the diamond trimmer thereon passes over the soft polishing pad and is included in polishing the wafer The diamond dresser passes over the soft polishing pad. 4. The method of trimming the chemical mechanical planarization polishing pad as described in claim 1, wherein the trimming arm having the diamond trimmer thereon passes over the soft polishing pad and is included in the middle of each wafer polishing The diamond dresser is passed over the soft polishing pad. 1303406 (2) * —咐—· You and your Mail 5 · $D ¥ Please refine the chemical mechanical planarization ii I ^ % method as described in item 1 of the patent scope, and further include a rotation against the soft polishing pad Wafer. 6 · % $ Please trim the chemical mechanical planarization iH _ % method as described in item 5 of the patent scope, and further comprise applying a slurry to the surface of the soft polishing pad. a chemical mechanical planarization system comprising: a head assembled in a housing; a wafer assembled to the head; a roller assembled in the housing; a soft polishing pad assembled to the roller, wherein a soft polishing pad for rotating on the drum; a pad dressing arm assembled in the housing; and a diamond dresser assembled to the pad dressing arm, wherein the dressing arm is configured to be applied via the diamond dresser A downward force of about 0.25 pounds (psi) to the soft polishing pad; and a water source to supply water to the soft polishing pad. 8. The chemical mechanical planarization system of claim 7, further comprising a slurry tank assembled in the housing. 9. The chemical mechanical planarization system of claim 8, further comprising a water tank assembled in the housing. 10. The chemical mechanical planarization system of claim 7, further comprising an electromechanical device assembled in the housing.