Papers by Keyword: Polish

Abstract: Wafer scratching from handling and processing can impact the performance of devices grown on a substrate. Knowledge of process conditions and modeling of scratches on wafers can be used to elucidate the root cause of scratches so that they can be eliminated.

Abstract: The impact of surface stress due to polish and grind processes on wafer bow was studied as a function of abrasive size. Results indicate that sub-surface damage from these processes can introduce significant surface stress. For polishing processes, this stress is proportional to mean abrasive size. The study also investigates stress as a function of depth below the wafer surface and finds that most stress is concentrated near the wafer surface.

Abstract: A nanoscale polish process with improved desired characteristics of low roughness and low scratch counts has been developed using a novel polish tape and diamond abrasive on hard glass substrates. For an improved polishing performance with high removal rate properties and preventing scratches, a novel tape was developed having a nanofiber level, densified surface and a flatter surface by slenderizing the fiber and dispersing ultrafine fiber using an innovative technique. Using this novel polishing tape with a fiber size of 200nm, one can produce a 17% lower surface roughness (Ra) (from 1.05A to 0.87A) and a reduced polished surface scratch count of 53 reduced to 18. The novel nanocluster diamond abrasive is synthesized from carbon atoms of explosives created by detonation in a closed chamber under an oxygen leaked atmosphere ambient. Several crystals are bonded together by layers of non-diamond carbon and other elements, forming aggregates with a nanocluster structure. Using this novel nanocluster diamond along with an ultra-fine diamond mixture with a nominal size of 15nm, one is able to produce an improvement of a 48% lower surface roughness Ra (from 0.87A to 0.45A) and a lower polishing surface scratch count reduced from 18 to 7. Overall, these results indicate that a smoother and a reduced scratch polished substrate results in a significant improvement in disk defects and related magnetic performances.

Abstract: The ceramics industry has been conducting numerous research studies with the objective of reducing and reusing waste to improve the quality and efficiency of the porcelain polishing process. Large amounts of residue are generated during the porcelain polishing process. Recycling this residue during the process itself reduces production costs. In this work, the residue of porcelain was characterised by thermogravimetric analysis (TGA), X-ray diffraction (XRD), X-ray fluorescence (XRF), linear retraction, water absorption, apparent density, apparent porosity and optical microscopy. Mixtures with different proportions of waste were obtained to evaluate at what proportion no loss of visual quality and structural material could be attained. Little structural or visual change was observed for samples that contained up to 2.0% porcelain residue by weight.

Abstract: In this paper, fuzzy AHP to select the appropriate environment-friendly chemical mechanical polishing additives, and the rational design of the polish formulation. Practical application shows that the polish has a good anti-wear, the wear properties and anti-rust properties, stable performance ，and meets the needs of the chemical mechanical polishing, the rate of biodegradation more than 80%.

Abstract: Large aspheric elements in giant laser facility are fabricated using computer controlled rapid polishing technology. The technological parameters are main influencing factors of efficiency. Base on Preston hypothesis, linear relationship of material removal with polishing pressure, polishing velocity and other conditions are established. According to the material removal function model of computer controlled rapid polishing, the removal function is simulated using MATLAB software. The influencing factors of volume removal efficiency are analyzed. In practice, the optimum polishing parameters are eccentricity 0.4, rotational velocity of principal axis 330 rpm, rotational velocity of polishing pad -600 rpm.

Abstract: The carbide drills with different edge preparation were used for drilling of 40Cr. The influence of drilling speed and amount of feed on drilling forces has been studied by the single factor experiment. The conclusions indicated: when the feed went bigger, the drilling forces of the polished drills were lesser than unpolished drills for un-coating drills; but for coating drills, the drilling forces of the polished drills were greater than unpolished drills. With the increase of cutting speed, drilling forces of un-coating drills mounted up first but went down afterward; and the drilling forces of coating drills increased monotonously.

Abstract: Shallow defects, which were induced by mechanical treatment, on 4H-SiC wafers were investigated. The density and the distribution in depth of shallow defects on the wafers were depended on wafer venders. Most of serious defects such as dislocation array (DA), triangular stacking fault (TRSF) and triangular defect (TRD) in epitaxial film were demonstrated to be caused by shallow dislocations on the surface of the wafers. Revised mechanical polish can reduce the densities of DA, TRSF and TRD in epitaxial film.

Abstract: With the rapid development of mobile communication technology, the short message name and address system [1] has been developed swiftly nowadays. We make the short message to be a kind of carrier, for delivering the requirements which clients required and return the answers which clients seek for. This paper contains such contents as follows based on the research of the system: analyzing the problems and defections existed in the system, enhancing the transfer mode to be a standard way, and improving the efficiency of data query and transfer. Taking advantages of the superiority of this system and innovate on the technology, we have completed a business software based on J2ME platform[2-7].In the research and development process we designed client-side functions and structural model combined with some functions used on the mobile phones, accordingly, the system technology has been practiced to some extents. And we optimize the software interface by a third party plug-in board called the “polish”, this work must will provide far-reaching significance for later research on this technology.

Abstract: Hard disk substrates play a key role in the data storage process of magnetic storage hard disk drives (HDDs). However, a potential failure mode exists with the head clearance requirements caused by surface variation which is induced by substrate nano-asperities. Consequently, developing a polish process to eliminate surface asperities and residual surface defects in the glass substrate disks process is therefore a necessity to meet the challenges of future technology. Currently, the leading candidate utilizes nano cluster diamond (NCD) abrasive which is a synthetic diamond created in a controlled explosion process. A great effort is now underway to modify these NCD clusters to reduce light scratches and asperities in the perpendicular magnetic recording media polish process. Three distinct diamond types of NCD-90, NCD-80 and NCD-70 were utilized in this study. The major difference among these three distinct cluster diamond types is the diamond percentage amounts. Because of the differing diamond percentage content, one achieves a different structure which changes the polish properties. HRTEM, XPS, Raman, BET, AFM, Optical Surface Analyzer and disk defect testers were used for the diamond particles, polished substrate and disk analysis. The detail shall be discussed in this study.