Aluminum metallization for SiGe devices

摘要

Single crystal aluminum is deposited on SiGe structures to form metal interconnects. Generally, a method of forming single crystal aluminum on Si(1-X)GeX is presented, including the steps of maintaining the substrate at certain temperature (e.g. between 300 DEG C. and 400 DEG C.) and pressure conditions (e.g. below 2x10-9 millibar) while aluminum atoms are deposited by a vacuum evaporation technique. This is apparently the first method of depositing single crystal aluminum on SiGe surfaces. Novel structures are made possible by the invention, including epitaxial layers 34 formed on single crystal aluminum 32 which has been deposited on SiGe 30. Among the advantages made possible by the methods presented are thermal stability and resistance to electromigration.