Resolution amplifier stability

For a good measurement, the amplifier should satisfy many requirements. Not all types of measurements, however, require the same level of performance. For example, if one measures only the number of particles and not their energy, the precision and stability of the amplification process can be relatively poor. It is in spectroscopy measurements, particularly measurements using semiconductor detectors, that the requirements for precision and stability are extremely stringent. Since the energy resolution of Ge detectors is of the order of 0.1 percent, the dispersion of the pulses due to the amplification process should be much less, about 0.01 percent. 

The concept of acid labile crosslinked units in polymers for positive DUV resist was evaluated with poly-(4-hydroxystyrene/4-vinylcyclohexanol) and implemented on a poly-4-hydroxystyrene backbone. The principle to increase the molecular weight by a transacetalization reaction was used to improve acetal protected phenolic resins for advanced chemically amplified resists. The polymer chains were linked via diols with acetal bridges. This type of linkage can be applied to a wide range of phenolic polymer binders. Resolution and thermal stability of the photoresist patterns were improved. Gel permeation chromatography and dissolution rate measurements prove that the crosslinked units remain essentially intact in the unexposed areas, thus enhancing... 

Whether manual or automatic standardization is employed, the criteria of this control are resolution, range, and stability. Often a meter which reads to 0.001 pH has two controls, coarse and fine, to provide the needed resolution. The range is typically 100 to 200 mV (>l-3 pH units) to offset aging electrodes with a high asymmetry potential or to standardize an ion-selective electrode to a particular value. The stability is indicated by the amplifier drift specification which is typically less than a millivolt in 12 hours. 

The width of the dip at the center of the Doppler amplification line is equal to the homogeneous linewidth 2F which may be considerably smaller than Aud. This fact has opened up strong possibilities for spectroscopy within the Doppler profile. Such a method has been used in experiments on measuring collisional broadening and isotope shifts and on stabilizing the laser frequency at the center of the amplification line. However, the spectral resolution in these experiments was limited by the homogeneous width 2/hom of the amplified spectral transition between excited states, which was relatively large. 

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