| Abstract: | Recent results are reviewed on synchrotron radiation (SR)-excited photochemical reaction studies aimed at applications to semiconductor processes. Valence or core electronic excitations induced by SR irradiation and ensuing chemical reactions are classified and characterized by rate equations. Unique material selectivity in etching has been found. SiO2 has been found to evaporate by SR irradiation and this phenomenon can be applied to the low-temperature surface cleaning of silicon. In the epitaxial growth of Silicon by ultrahighvacuum chemical vapor deposition using Si2H6, SR irradiation significantly lowers growth temperature beyond the low-temperature limit of thermal reaction. Lowering of the operating temperature by SR irradiation is especially effective in applications to the atomic layer epitaxial growth of silicon. The layer-by-layer process has been successfully demonstrated, confirming self-limiting adsorption of SiH2Cl2 and ensuring surface reactivation by SR irradiation. |
