The elastic modulus and transverse bend strength of pure, dense alumina specimens were determined as a function of grain size (1 to 250p) and temperature (30" to 1500°C). The elastic modulus was essentially independent of grain size over the temperature range covered. The transverse bend strength for fine-grain-sized alumina was substantially greater than that for larger-grain-sized alumina over the entire temperature range, although, at the highest temperatures, the rate of decrease of strength with temperature was greatest for the he-grained material. Fine-grained alumina (1 to 2 p ) exhibited considerable yielding and nonlinear load-deflection behavior at 1000°C and above. At 150OoC, the 1-to 2-p specimens bent to the limit of the apparatus without fracturing (approximately 7% outer-fiber strain).

This paper presents measurements of capacitance−voltage, Hall−effect, and diode characteristics on nitrogen−implanted silicon as a function of anneal temperature. The results of these three types of electrical measurements are consistent and show that less than 1% of the implanted nitrogen exhibits donor effects following anneals in the temperature range ∼700−900 °C. Hall−effect measurements performed as a function of temperature indicate that nitrogen in silicon has an ionization energy of 0.017±0.002 eV. Room−temperature Hall−effect measurements combined with stripping techniques have shown that the distribution of electrically active nitrogen is constant as a function of implantation depth. These results are believed to be due to a donor (substitutional) position involving <1% of the implanted nitrogen ions; this interpretation is consistent with the lattice location and damage results presented in Paper I.

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