Silicon crystals for future requirements of 300 mm wafers

Today, the main challenge in Si crystal growth development is the transitio n from 200 to 300 mm diameter. While the complexity of the growth process i ncreases with larger charge size and crystal diameter, the perfection of th e growth process must significantly improve to avoid any disturbances that result in structure loss during growth and, hence, cause massive material l osses. With regard to the future bulk quality, radical changes may be requi red as the design rule approaches the size of the prevailing grown-in defec t type. Therefore, grown-in defect free wafers will be required, which can be produced either directly by pulling, by wafer annealing or by epitaxy. A s substrates for annealed and epitaxial wafers, nitrogen doped and fast pul led crystals provide sufficient internal gettering capability in low therma l budget device processes. Moreover, grown-in defects in nitrogen doped cry stals are so small that they are easily covered during epitaxy or annealed during high temperature treatment. (C) 2001 Elsevier Science B.V. All right s reserved.