Slurry conditioner

An alternative method to filtration has been considered in order to reduce the large particles and agglomerates. Li and co-workers [41] investigated a novel slurry conditioner to reduce the oversized particle count present in CMP slurries. This study focused on the correlation between the oversized particle counts in STI CMP slurries and their influence on the wafers after polishing. A representative oversized particle count reduction after the treatment with the conditioner is shown in Fig. 13.30. 

FIGURE 13.30 Representative changes in the large (a) and small (b) particle size volume distributions before and after treatment with the imation CMP slurry conditioner. 

FIGURE 13.31 Representative defect counts for STI wafers polished with imation slurry conditioner. STI-1 is a ceria-based slurry and STI-2 is a silica-based slurry. 

Figure 13.30a shows a significant change after treatment with the imation CMP slurry conditioner in the oversized particle volume distribution, where the mean particle size of 120-125 nm was unaffected as shown in Fig. 13.30b. Therefore, the imation CMP slurry conditioner is capable of reducing the number of oversized particle count without influencing the mean slurry particle size and size distribution.

Most carbide acetylene processes are wet processes from which hydrated lime, Ca(OH)2, is a by-product. The hydrated lime slurry is allowed to settle in a pond or tank after which the supernatant lime-water can be decanted and reused in the generator. Federal, state, and local legislation restrict the methods of storage and disposal of carbide lime hydrate and it has become increasingly important to find consumers for the by-product. The thickened hydrated lime is marketed for industrial wastewater treatment, neutrali2ation of spent pickling acids, as a soil conditioner in road constmction, and in the production of sand-lime bricks. 

Tricalcium Phosphate. Commercial tricalcium phosphate (TCP) is actually an amorphous basic calcium phosphate close to hydroxyapatite in composition. Because of its extremely low solubiUty in water, TCP is precipitated almost quantitatively from dilute phosphate solutions with a slurry of hydrated lime. TCP is separated by dmm-, spray-, or flash-drying the TCP slurry, with or without intermediate sedimentation or filtration steps. It is used as an industrial-grade flow conditioner and parting agent. 

FIGURE 3.13 Several methods to control the polishing profile such as process conditions, carrier design, pad roughness, conditioner (dresser) design, and slurry. 

The chemical-mechanical polishing or planarization (CMP) process is a complex interplay between the wafer and the consumables involved. The consumables include slurry, pad, conditioner, and so on. During polishing, the pad carries the slurry and delivers it to the wafer surface. It also transmits the normal and shear forces from the polisher to the wafer. Therefore, polishing pad plays a critical role in the CMP process and influences the outcomes such as material removal rate (MRR), within-wafer nonuniformity (WIWNU), wafer-to-wafer nonuniformity (WTWNU), step height reduction efficiency (SHRE), and defect counts. 

The supply of the coppice will be undertaken by Yorkshire Environmental Ltd., which will try to maximise the utilisation of biomass fuels supplied by short rotation forestry. Slurry of domestic treated sewage sludge supplied by Yorkshire Wafer Services Ltd. will be applied to the coppice plantations as organic fertiliser to increase crop yield. The sludge will be low in heavy metal, pathogens and odour. Waste ash from both the gasifier and the catalytic cracker will be recycled to the coppice plantations as a soil conditioner and source of base cations and micronutrients to improve soil fertility. 

Some of these results are in marked contrast to other observations that indicate an increase in MRR value with increased conditioner downforce.12 13 In this study the MRR was examined against variations in conditioner down-force, slurry abrasive type (fumed or colloidal), conditioning approach (in situ or ex situ), and pad slurry distribution support geometry (perforated or grooved). Results indicated a strong positive correlation in nearly all cases between conditioner downforce and MRR (Figure 7.15). 

Figure 7.17 Polishing rate saturation with different slurries for various conditioners.10...

The purpose of the conditioning disk is to present the conditioning abrasive to the pad surface in a way that will deliver the necessary pad conditioning effects. Currently, all three of the required effects are treated as a single effect and handled through physical abrasion of the pad surface with a diamond-studded end-effecor (called a disk). The use of diamonds is necessary because of the extreme hardness of the abrasives used in the slurry. The presence of such abrasives on the pad would rapidly wear down materials softer than diamond. Several major suppliers of diamond conditioner disks are available, each one with its own combination of disk properties. A variety of physical disk formats is available, from solid disks to open patterns (such as ribbed or honeycomb shapes). Likewise a variety of ways to bind the diamonds to the disk exist, and they impact disk lifetimes and possibly wafer scratch damage. There is also a choice of diamond types, which affects the shape of the abrasive as it protrudes from the disk surface. 

CAS 14807-96-6 EINECS/ELINCS 238-877-9 Uses Filler tor chem., foods, paper, agric., paints, and other industries carrier, diluent, conditioner, grinding aid in pesticides Properties Lt. gray po d. 6.6 median particle size 3% on 325 mesh sp.gr. 2.4 bulk dens. 12.8 Ib/tP surf, area (BET) 190 trf/g water absorp. 220% oil absorp. 170% brightness (Photovolt) 54 ref. index 1.54 pH 7.6 (10% aq. slurry)... 

Hazardous Decomp. Prods. Heated to decomp., emits toxic vapors of NOx Uses Foam booster/stabilizer, wetting agent, thickener, conditioner, softener, germicide, dispersant, antistat for shampoos, detergents, pickling baths, foods, textiles rinse aid in cosmetics extraction aid in fermentation corrosion inhibitor, emulsifier, softener in detergents flow conditioner in heavy-duty detergent slurries... 

Bisisostearamidopropyl ethoxyethyl dimonium chloride C12-14 alkyl dimethyl betaine Cocobetaine Hydrogenated lanolin Jsostearyl ethylimidonium ethosulfate Lanolin wax Quaternium-18 Sodium isostearoamphopropionate Soyamidopropyl dimethylamino gluconate conditioner, industrial cleaners Sodium cocoamphopropionate Soyamide DEA conditioner, industrial processes PPG-40 diethylmonium chloride conditioner, industrial slurries PPG-9 diethylmonium chloride conditioner, institutional laundry Distearyidimonium chloride conditioner, janitorial prods. Isostearamidopropylamine oxide Myristamine oxide Oleamidopropylamine oxide ... 

It is common practice to add the etheramines, which are partly neutralised (5-30%) with acetic acid, direct to the mineral slurry. As in all flotation operations, the collector is sensitive to slime in iron ore applications, and in particular for haematite, a lot of fine material is produced during the grinding process. The presence of slime will increase the collector consumption drastically, and give poor silica reduction and decrease the iron recovery. Therefore, a de-sliming stage is often used prior to flotation. In this, the iron oxide particles are depressed with starch or dextrin alkalized com starch is also commonly used. The depressant is added in a conditioner formulation before the collector is added. The pH varies between 8 to 10.5 in haematite flotation, with 10.5 being the common pH used, while magnetite flotation often takes place at pH levels of 8 to 10. 

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