In situ silicon-wafer temperature measurements during RF argon-ion plasma etching are reported for four different wafer cooling environments: (i) lying on the electrode; (ii) clamped to the electrode; with additional helium gas between wafer and electrode in both (i) and (ii), in order to enhance heat transfer. Fluoroptic thermometry is applied to measure the local surface temperature of the wafer during plasma processing. The measured heating and cooling curves can be fitted using a model which considers conductive heat losses only. Deviations are observed when high RF power is applied and surface temperatures higher than 120 degrees C are reached. The authors report on effective cooling via helium gas of the rear side of the wafer which is lying on an electrode without any clamping.

The drift mobilities for electrons and holes in vitreous Se were measured as a function of temperature and as a function of the applied electric field. The drift mobilities exhibited a temperature dependence not previously observed. The electron drift mobility exhibited an exponential temperature dependence up to the glass transition temperature (T g = 305°K.). At this point, a sharp break from the exponential temperature dependence was observed. Below 305°K, the electron drift mobility exhibited an exponential temperature dependence which is characteristic of a trap-limited drift process. In this temperature range, the computed mobility-controlling electron trap densities and the measured activation energies depended on the temperature of the substrate at which the selenium films were prepared. It is shown that as the substrate temperature is increased, the activation energy for the mobility increases, and the density of the traps which control the mobility decreases. The hole drift mobility exhibited an exponential temperature dependence at low temperatures, but a gradual deviation from the exponential temperature dependence at a temperature of about 260 °K was observed. This indicates that the microscopic hole mobility fxo p has a low value. The microscopic hole mobility, evaluated at 293°K, yielded an average value of juo2>=0.34 ±0.05 cm 2 V _1 sec -1 . In the low-temperature range the hole trap densities and the activation energies were computed. These quantities revealed the same dependence on the substrate preparation temperature as the corresponding quantities for electron transport. It is postulated that the mobility-controlling traps are caused by the disorder in the amorphous selenium. The electron and hole drift-mobility values at room temperature agreed with previous measurements.

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The influence of power and substrate temperature on the chemical composition of inductively coupled RF plasma‐polymerized films of acrylonitrile was monitored by ESCA. At a substrate temperature of 20°C a minimum in nitrogen content as a function of power was observed for films deposited in the coil region. A maximum was observed for a substrate temperature of 150°C. When power was increased from 1 to ∼50 W a linear increase in nitrogen content was observed in the tail region at both substrate temperatures. A step function observed in the C1s and N1s core‐level spectra is discussed in terms of extensive unsaturation being present in the films.