No abstract

The characteristic parameters of a solid-to-solid diffusion system are investigated. The net boron concentration of the pyrolytically deposited SiO2 films used as diffusion sources is determined by infrared spectrophotometry. The data of the diffused layer in Si are used to correlate the infrared absorption spectrum with the composition of the SiO2 films. The absorption cross section of the B-O oscillator is determined. The surface concentration and junction depth of the diffused layer in the Si are determined from the infrared absorption of the SiO2 film and by the four-point probe and bevelled-edge methods.

An improved version of time‐resolved TEM is described which detects electron pulse‐induced phase transitions with a resolution of 3 ns in specimen areas above 0.3 μm Ø. The heating pulse automatically is switched off within 15 ns after the phase transition is detected. Using a train of needle pulses the specimen also may be probed outside or after the heating pulse. The method is applied to pulse annealing of amorphous Ge and Ge0.6Te0.4 films by electron beams depositing ≈ 1 kW/cm2. Formation times of crystals are determined (5 to 10 ns) and fast disintegration and recrystallization is traced. Pronounced thermal aftereffects are observed, triggering even crystallization within several μs after the end of the heating period.

The composition, refractive index and thickness of thermally grown SiO~ layers grown onto Si single erystals were investigated by attenuated total refleetion speetroseopy (ATR) and ellipsometry. Under laboratory storage conditions the value of the refraetive index proved to be time dependent. A saturated water vapour treatment at 79~ showed that the change in refractive index was caused by a small quantity of water vapour absorbed by the layer. A difference in the SiO2 absorption band between 1050 cm -1 and 1200 cm -1 was observed if the measurements were made by transmission of ATR techniques. In the ATR speetrum an absorption band beeomes visible which is seen in the transmission spectrum only asa slope.By changing the angle of ineidenee the distribution of the radiant power within the layer could be influenced. So ir was possible to draw conelusions as regards the inhomogeneity of the layer by a nondestruetive method.