Semiconductor Wafer Processing

Reactive Hquid infiltration (45,68,90,93,94) is similar to the CVI process used to make RBSN. Driven by capillarity, a reactive Hquid infiltrates a porous preform and reacts on free surfaces. Reactive Hquid infiltration is used to make reaction bonded siHcon carbide (RBSC), which is used in advanced heat engines and as diffusion furnace components for semiconductor wafer processing. 

Use For chromatography, pesticide, residue analysis, spectrophotometry, and semiconductor wafer processing. 

The performance of semiconductor devices may be altered by the presence of contamination before, during and after device fabrication. Because of this. It Is necessary to achieve the highest degree of cleanliness possible during semiconductor wafer processing. There are many cleaning procedures and the most desirable process will depend on which step In device fabrication It follows and which step It precedes. This paper reviews the current... 

Figure 5.15. Graphite barrel holder for semiconductor wafer processing. (Photograph courtesy Sigri Great Lakes Corp., Niagara Falls, NY.)...

The fabrication method generates functional elements via anisotropic etching of high-quality semiconductor wafers, referred to as mother wafers.13 17 25 The process begins with photolithographic definition of patterns... 

Wright of Advanced Micro Devices discusses the use of Raman microspectroscopy to measure the integrity of a film on semiconductor wafers during manufacture in US patent 6,509,201 and combined the results with other data for feed-forward process control [181]. Yield is improved by providing a tailored repair for each part. Hitachi has filed a Japanese patent application disclosing the use of Raman spectroscopy to determine the strain in silicon semiconductor substrates to aid manufacturing [182]. Raman spectroscopy has a well established place in the semiconductor industry for this and other applications [183]. 

The cost per CMP wafer pass is high when compared to other semiconductor manufacturing processes. This aspect of CMP reflects the rapid transfer of CMP into production, as well as the large amount of slurry and pads that are consumed during CMP. CMP CoO has improved in the last few years due to several factors. 

Electrochemical properties of silicon single crystals, usually cuts of semiconductor wafers, have to be considered under two distinct respects (1) As an electrode, silicon is a source of charge carriers, electrons or positive holes, involved in electrochemical reactions, and whose surface concentration is a determining parameter for the rate of charge transfer. (2) As a chemical element, silicon material is also involved in redox transformations such as electroless deposition, oxide generation, and anodic etching, or corrosion processes. 

What is accomplished by adhesion promotion treatments in IC manufacturing should actually be referred to as wafer substrate preparation, and not adhesion. Adhesion in the structural sense, as experienced in airplane composite material parts attachment, is not accomplished by silane wafer processing treatments except for the PI applications discussed early in this paper. The term adhesion, as it is used here, refers to a more practical definition—that is, resist image adhesion. Nevertheless, this type of adhesion is essential to the huge international semiconductor business, and the early silane work of Plueddemann and others was essential to early wafer adhesion process development. 

FTIR analyzers for semiconductor wafer quality testing is an example, as mentioned below. Today we speak of process analytical instrumentation (PAI), and we use the term PAI which relates to the totally integrated system, implemented on-line, and made up of some or all of the following components. 

Wright of Advanced Micro Devices, Inc. discusses the use of Raman spectroscopy to measure the integrity of a film on semiconductor wafers during manufacture in US patent 6,50 9,201.87 The Raman measurements are made during the manufacturing process and can be considered an on-line system. Unlike many process Raman installations, this one is based on micro-Raman, where a microscope is used to focus the laser beam to a spot only a few micrometers in diameter. The Raman data is combined with other measurements, such as scatterometry, to calculate a stress level and compare it to... 

Modifed PTFE can be used in practically all applications, where the conventional polymer is used. In addition to that, new applications are possible because of its improved flow and overall performance. In the chemical process industry, it is used for equipment linings, seals, gaskets, and other parts, where its improved resistance to creep is an asset. In semiconductor manufacturing, modified PTFE is used in fluid handling components and in wafer processing components. Typical applications in electrical and electronic industries are connectors and capacitor films. Other applications are in unlubricated bearings, laboratory equipment, seal rings for hydraulic systems, and antistick components.103... 

The current analytical capabilities of ICP-MS provide a means to assess new low levels of contamination in the semiconductor industry [385]. Contamination in clean room air can be detected at very low levels. Dopant and trace metal contamination on semiconductor wafer surfaces can be monitored. Ultratrace metals in deionized water, high-purity acids, and other process chemicals can often be measured at concentrations less than 1 part per trillion. 

Wet cleaning of wafers during the semiconductor production process often requires uniform removal of a few nanometers of material. Ideally, a single cleaning chemistry can be found that etches all exposed features at a comparable rate. Etch rates near 1 nm/min are desired for batch process and near 10 nm/min for single-wafer processes. A mixture of 500 1 DHF (dilute HF) with dissolved oxygen controlled near parts-per-million (ppm) levels has been found to meet these requirements for post copper CMP (chemical-mechanical polishing) cleans with exposed SiOj and Cu metal. 

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