LOW-RESISTANCE OHMIC CONTACTS TO P-GE1-XCX ON SI

We report on ohmic contact measurements of Al, Au, and W metallization s to p-type epitaxial Ge0.9983C0.0017 grown on a (100) Si substrate by molecular beam epitaxy (MBE). Contacts were annealed at various tempe ratures, and values of specific contact resistance have been achieved which range from 10(-5) Ohm . cm(2) to as low as 5.6 x 10(-6) Ohm . cm (2). Theoretical calculations of the contact resistance of metals on G e1-xCx with small percentages of carbon, based on the thermionic held emission mechanism of conduction, result in good agreement with the ex perimental data, We conclude that Al and Au are suitable ohmic contact s to p-Ge0.9983C0.0017 alloys.