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A short period low-temperature-annealing procedure is proposed for the two step annealing process to make effective intrinsic gettering in silicon device processing. A continuous raising of annealing temperature at a constant rate during the low temperature annealing step increases the density of bulk microdefects which are able to grow further in the subsequent high temperature device processing step. The temperature raising rate is limited so that the expanding speed of the critical size of microdefects at the annealing temperature is lower than the growth rate of microdefects. The optimum defect density is discussed from the standpoint of wafer warpage and gettering ability.

Bi-substituted rare-earth iron garnets, (REBi) 3 Fe 5 O 12 (REBiIG), are used in wide-band optical communication as Faraday rotators in an optical isolator. However, the influence of rare-earth ions on the magneto optical (MO) properties of REBiIG crystals, such as specific Faraday rotation (FR) and coercive force, is not clear. The aim of the present work is to compare the MO properties of garnets doped with different rare-earth ions. REBiIG (RE ¼ Ho, Yb, or/and Tb) crystals were grown from Bi 2 O 3 self-fluxed melts by the top-seeded solution growth method under the same conditions. It was found that both specific FR and coercive force decrease with an increase in rare-earth ion radius. The FR wavelength stability of HoYbBiIG is better than that of YbBiIG but worse than that of HoBiIG. However, the FR temperature stability of HoYbBiIG is worse than that of YbBiIG but better than that of HoBiIG. It is noted that HoYbBiIG crystal is a trade-off between HoBiIG and YbBiIG crystals in terms of MO properties.

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The resistance of precipitation-treated Czochralski-grown silicon wafers to warpage has been investigated using crystals containing oxygen at a concentration of 5.5-12.3×1017 atoms/cm3. The precipitation softening is effectively suppressed if the oxygen concentration is lower than a threshold value of about 8×1017 atoms/cm3. In wafers with oxygen concentrations of 5.5-8×1017 atoms/cm3, oxygen precipitation proceeds slowly, resulting in slow growth of bulk stacking faults and few dislocation sources. In MOS image-sensor devices, the wafers with such oxygen concentrations have few crystal defects within the area of the photodiodes after processing, which cause the fatal failure of white blemishes detected as white scratches on output pictures.