Effect of Dressing Load and Speed on Removal Rate in the Chemical Mechanical Polishing Process

A pad conditioner or diamond disk is needed to regenerate the asperity structure of the pad and recover its designated role in the chemical mechanical polishing process. In this paper, the effect of dressing load and speed on removal rate of oxidized wafers were investigated using a polycrystalline diamond disk and brazed diamond disk. It was found that polycrystalline diamond disk enable the manufacturer to tightly control diamond leveling and the cutter’s shape by comparison with a brazed diamond disk that contains discrete diamond grits of random orientation. Experimental results revealed that for polycrystalline diamond disk, the removal rate of oxidized wafer displayed an almost unchanged curve when the load was less than 4kg, but the removal rate of oxidized wafer for brazed diamond disk initially increased with the dressing load, reaching a maximum value at a dressing load of approximately 4 kg. Then, it decreased slowly with further increases of the dressing load. The removal rate of oxidized wafer remains unchanged with dressing speed.

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Combined Diamond Disks in Chemical Mechanical Polishing

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.642.110 ◽

2015 ◽

Vol 642 ◽

pp. 110-114

Author(s):

Ming Yi Tsai ◽

J.K. Ho ◽

Jyu Lin Zeng

Keyword(s):

Chemical Mechanical Polishing ◽

Diamond Crystal ◽

Removal Rate ◽

Mechanical Polishing ◽

Experimental Results ◽

Polishing Process ◽

Diamond Grit ◽

Diamond Disk ◽

Crystal Shapes ◽

Chemical Mechanical Polishing Process

This paper presents a combined diamond disk that is designed and manufactured to markedly improve the leveling of diamond tips, thereby reducing the amount of diamond grit. First, a small brazed diamond disk was manufactured. Second, 12-or 24-disk brazed diamond disks were mounted onto a substrate with a diameter of 108 mm for completing the combined diamond disk. Four types of disks were fabricated, and their performances were compared with that of a conventional diamond disk. The experimental results showed that the combined diamond disk has more complete diamond crystal shapes and distribution with better leveling, which increases the effectiveness of the working diamond grits. Compared to a conventional diamond disk, the combined diamond disk achieved a higher wafer removal rate and better uniformity while consuming less pad material. The number of diamond grits required was significantly lower. Roughly, 7,600 and 12,000 diamond grits were used for the 24-and 12-disk brazed diamond disks, respectively, in the new disk, whereas 20,000 diamond grits were used in a conventional diamond disk. In the case of the conventional diamond disk, the diamond tips are leveled to more than 50 μm. However, in the case of the combined diamond disk, the diamond tips can be leveled to less than 30 μm because the diamond tips are already leveled. These results contribute to the understanding of conditioning techniques and further improvement of the chemical mechanical polishing process.

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Investigation of the Wear of the Pad Conditioner in Chemical Mechanical Polishing Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.76-78.195 ◽

2009 ◽

Vol 76-78 ◽

pp. 195-200 ◽

Cited By ~ 2

Author(s):

Yunn Shiuan Liao ◽

C.T. Yang

Keyword(s):

Experimental Data ◽

Chemical Mechanical Polishing ◽

Wear Behavior ◽

Removal Rate ◽

Mechanical Polishing ◽

Polishing Process ◽

Diamond Disk ◽

Flat Substrate ◽

Chemical Mechanical Polishing Process ◽

Outside Diameter

The pad surface will become grazed because of the accumulated debris in the chemical mechanical polishing (CMP) process. It results in the reduction of the wafer removal rate, and a pad conditioner or diamond disk must be frequently employed to refresh the pad surface. The wear behavior of a diamond with respect to its location, original relative protruded height and protruded shape on a diamond disk was investigated in this thesis. It was found from experimental data that the diamonds which were located outside, originally protruded more highly and with crest lines oriented upward wore faster. Accordingly, four suggestions were proposed to obtain the uniform diamond wear. They are: lowering the protruded heights of the outside diamonds, replacing the current flat substrate by a curved surface substrate, changing the diamond distribution on the disk from the current uniform one to a higher concentration around outside diameter, and orienting the diamonds such that the flats are protruded upward for the outside diamonds and the crest lines are projected upward for the inside diamonds. Experiment had verified that the pad conditioner with center-protruded substrate led to a stable and higher dressing rate.

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Friction Phenomenon in Chemical Mechanical Polishing of Oxide Film

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.126-128.320 ◽

2010 ◽

Vol 126-128 ◽

pp. 320-325

Author(s):

Ming Yi Tsai ◽

W.Z. Yang

Keyword(s):

Oxide Film ◽

Friction Force ◽

Chemical Mechanical Polishing ◽

Removal Rate ◽

Polycrystalline Diamond ◽

Mechanical Polishing ◽

Interface Temperature ◽

Diamond Disk ◽

The Coefficient Of Friction ◽

Diamond Conditioner

The friction phenomenon was investigated to explore the relationship between the diamond conditioner, polishing pad and wafer of oxide film in the chemical mechanical polishing (CMP) process. Two kinds of diamond conditioners (disk-A and disk-B) were used. Diamond disk-A used was traditional diamond conditioner containing random shaped diamond grits. Diamond disk-B used was made by sculpturing a sintered polycrystalline diamond to form identically shaped cutting tips. Experimental results reveal that friction force between disk and pad increases with dressing load. But friction force decreases with sliding speed due to increase of sliding speeds resulting in an increase of interface temperature. The coefficient of friction between wafer and pad initially increases with the dressing load, and then it starts to drop slowly with further increases of the dressing load. It was found that removal rate of the oxide film correlates well with the variation of the coefficient of force. In addition disk-B can produce a higher wafer removal rate under a low dressing load.

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Study on the Effect of Nano-SiO2in ULSI Silicon Substrate Chemical Mechanical Polishing Process

Journal of Nanomaterials ◽

10.1155/jnm/2006/25467 ◽

2006 ◽

Vol 2006 ◽

pp. 1-4

Author(s):

Liu Yuling ◽

Wang Juan ◽

Sun Ming ◽

Liu Chenglin

Keyword(s):

Silicon Substrate ◽

Chemical Mechanical Polishing ◽

Ph Value ◽

Removal Rate ◽

Low Ph ◽

Mechanical Polishing ◽

Polishing Process ◽

Chemical Mechanical Polishing Process ◽

Traditional Function

Both process and mechanical of silicon substrate chemical mechanical polishing (CMP) are studied in detail, and the effects of experiments designed indicate that nano-SiO2grinding particles seem to be acted as catalyzer besides the grinding action during the CMP process. This is different from the traditional function. As a result, in the condition of low pH, the nano-SiO2slurry can be recycled. In the meanwhile, the removal rate can gain stability and pH value does not change obviously.

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