Plasma ashing

Low-frequency plasma ashing and the other techniques such as the Trace-O-Mat products have been developed at the University of Graz, Austria. Commercial developments outside Austria and Germany have been slow owing to the need for manual involvement. Further details on these products can be found in the publication by Knapp et al. [51]. 

Small Data Set. Low-temperature (plasma) ashes (LTAs) were obtained from ten diverse coal samples (Table I), ranging in rank from lignite to Ivb. Infrared spectra were obtained of duplicate samples of each LTA. A separate set of duplicates generated (for other purposes) for the first four LTAs listed also was analyzed by FTIR. 

Methods. Coals ground to -60 mesh were low-temperature (O2 plasma) ashed in one of three plasma ashers to constant weight for about... 

Minimal (Sample on Ground Plane) Plasma Cleaning Plasma Anodization (Oxygen plasma) Plasma Etching Plasma Ashing (Oxygen plasma)... 

Current commercial plasma-enhanced CVD reactors operate with only two physical concepts. In one case, we have the inductively-excited discharge in a tube, which is used for plasma ashing of resist. The other is the parallel plate arrangement using high-frequency RF power to create a low-pressure glow discharge, where the wafers to be coated sit on one of the electrodes. 

This patterned substrate was exposed to plasma for removal of the monolayer (Fig. 10.5d). The resist pattern was used as the mask for plasma ashing. After this process, photo-resist was removed and the amino silane monolayer was formed on the exposed clean oxide layer (Fig. 10.5e). 

FIGURE 52 Large catalyst fragment obtained by plasma ashing of polymer. 

We used two plasma ashing devices International Plasma Corporation, Model 1003B-248AN and LFE Corporation, Low Temperatures Asher, No. LTA-600.) Since the plasma combustion temperature does not exceed 50°C we avoid the possibility of mineral decomposition (especially of carbonates) encountered during high temperature combustion. 

Bomb combustion or digestion Oxygen plasma ashing... 

Wole W, Mertz W and Masironi R (1974) Determination of chromium in refined and unrefined sugars by oxygen plasma ashing fiamdess atomic absorption. J Agric Food Chem 22 1037-1042. 

Acid digestion of oxygen plasma ashing extract with polydi thi ocarbanate resin measure at 213.9 nm... 

By using photoresist as a sacrificial layer or structure, further processes, etching, ion implantation, molding, lift-off, and so on, may be performed. When patterned photoresist finish its roles, it is better to be removed from substrate. There are two kinds of methods to remove photoresist layer, wet type and dry type. Wet type photoresist removal process requires the chemical, PR remover or PR stripper, which can dissolve photoresist. Alternatively, plasma ashing process may remove photoresist This process is called dry process and uses oxygen plasma which oxidizes photoresist layer. 

In order to avoid photoresist deposition over severe topography, a peeling mask (nested mask) can be used two mask patterns are fabricated on a starting surface, using a suitable combination of mask materials, e.g., oxide-resist or oxide-nitride. After the first DRIE step, one of the mask materials is selectively removed (oxygen plasma ashing of resist mask or HF etching of... 

Some authors recommend direct ashing in a tantalum boat in the graphite furnace [52] plasma ashing is rarely used [53]. The most usual decomposition medium is nitric acid, with or without added H2O2 or H2SO4. 

FIGU RE 1.22 Electron microscope images of the tracks (a) irradiating from aparticle containing uranium (b) and the energy-dispersive x-ray spectrum of the particle after plasma ashing (c). (Adapted from Esaka, F. et al Anal. Chim. Acta, 721,122, 2012. With permission.)... 

In integrated circuit fabrication, novolac-based photoresist is used as a mask to define selectivity areas to be ion implanted. The implanted photoresist does not remain a part of the device structure and must be removed. Removal of implanted photoresist is extremely difficult because of its high degree of chemical resistance and is accomplished by harsh chemical treatment, such as with sulfuric peroxide, or by plasma ashing [23]. The toughness of implanted polymers presents a problem in this application, but it is just this chemical resistance that enables their photolithographic processing. 

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