Use as resist

Recent developments are leading toward other materials like silica gel or polymers. Certain types of semiconductors are also used as resistive probes. The measurement range of resistive sensors varies depending on materials used. It can be as wide as 0-99% RH. The dynamics are fast enough for normal ventilation applications and the stability of good resistive sensors is high. This does not reduce the need for calibration, but the intervals of successive calibrations can be extended. 

NTD (neutron transmutation doped) germanium chips are used as resistive thermometers in low-temperature detectors/calorimeters. 

TABLE 1. Physical Properties of Selected Step 5 Polymers Used as Resist Materials in Lithographic Applications 1... 

Some researchers, aware of the temperature problem, elect to use electrically heated wires for heat sources. The same wires can be used as resistance thermometers with satisfactory accuracy. A drawback, however, is that tests cannot be made in the transition region of boiling, because of instability. In addition, unless the wires are quite small the currents needed become very great. For example, if a -in.-diam. copper tube with a 0.03-in. wall is intended for use with water near the critical AT, a current of about 8,000 amp. is required. 

In CF4 plasma etching at 0.5 to 1 Torr pressure, the active species are neutral free radicals like F atoms and CF3 (28). Novolak resins have fairly strong CF4 plasma etch resistance (29), which, because of widespread use of the dry etching process, is one of the required features for resins used as resist materials for IC manufacturing processes. 

Nichrome, 80% Ni, 20% Cr (several types with variations of these percentages and additions of other elements, such as silicon in small amounts), is used as resistance wire for heating elements. 

Chromel, 35-60% Ni, 16-19% Cr, generally with the balance Fe, also is used as resistance wire and for thermocouples. 

In addition to conventional photoresist polymers, Langmuir-Blodgett (LB) films and SAMs [79-81] have been used as resists in photolithography. In such applications, photochemical oxidation, cross-linking, or generation of reactive groups are used to transfer micropatterns from the photomask into the mono-layers [82-84]. 

In electronics, fluoroacrylates are used as resists in high-density electronic integrated circuits, and as protective coatings in printed circuit boards.29 They are also often used in xerographic process for negative charge control.30... 

Valentini et al. [49] demonstrated that the three-dimensional hairlike CNFs can be used as resistive gas sensors for NO2 detection as well. A vertically aligned film with individual CNFs heavily entangled with each other is deposited between two Pt interdigital electrodes by PECVD. Because of the large diameter and abundant defects of these CNFs, the dopant effect due to the charge transfer between CNF and the NO2 adsorbates should be small. The adsorbed NO2 molecules may intercalate between the contact points of neighboring CNFs to contribute to the resistance change. 

The application of the modem theory of valency in organic chemistry has led to new remarkable formulations of many compounds, such as ethylene and benzene, two main building blocks of materials used as resist resins in lithography. Today,... 

Polysulfones have found use as resists in the area of mierolithography since the polysulfones are unstable toward radiation and heat below their melting points and the SO2 and olefin degradation products are volatile. It is interesting to note that some olefins undergo isomerization during the radiation induced degradation step [9c]. 

Metals, as well as semiconductors have been used as resistance thermometers. As given in Fig. 4.5, the conductivity depends upon the number of charge carriers n, their charge e, and their mobility p. The mobility of the electrons is impeded by the... 

Angelpoulos et al. [275,276] have reported a very interesting application of emeraldine base for lithography. Emeraldine base has been used as resists, and the authors used emeraldine base solution in NMP mixed with triphenyl sulphonium hexafluoro antimonate. This solution was used to spin-coat thin films on quartz and silicon wafers. On exposure to ultraviolet radiation of... 

The one-point mutated ALS except for the mutation of serine at position 627 to isoleucine exhibited a high resistance to the SU herbicide, chlorsulfuron. On the contrary, the resistance level of these mutated ALS s to the IM herbicide, imazaquin, was lower than that of chlorsulfuron. The mutation of proline at position 171 to alanine and histidine did not confer resistance to imazaquin. On the odier hand, the resistance level of die proline mutated ALS s to the PC herbicides was moderate between diose of chlorsulfuron and imazaquin. These results were correlated to the cross-resistance pattern of the proline-mutated ALS of K. scoparia as already described. From these results, it is considered that rice mutated recombinant ALS s, especially the proline mutants, are useful as resistant enzyme models for the herbicide resistance management at newly developed or developing ALS-inhibiting herbicides. We are now preparing other kinds of proline mutants to confirm this idea. 

Recently, considerable attention has been paid to polysilanes not only because of their potential usefulness as resists but also because of their unusual photochemU cal and photophysical properties (i). For example, the measurements of photoconductivity indicate the existence of very high mobile positive carriers (2). However, the electronic states of charged carriers have not been revealed yet. 

RS, resistant starch RSi, physicaiiy inaccessibie starch RSa, resistant granuies RS3, retrograded starch. KOH and dimethyi suifoxide are used as resistant starch soiubiiizing agents. 

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