Ohmic Contacts to Lightly Doped Silicon Using Rare Earth Metals
Original Publication Date: 1982-Sep-01
Included in the Prior Art Database: 2005-Feb-10
A new class of ohmic contacts to silicon is described. Rare earth metals and yttrium are shown to have barrier heights which are low with respect to Si; the low barrier height also implies a low contact resistance structure. The lowest barrier observed on p-type Si is that formed by PtSi with Phi Beta(-4)=0.25 eV.(2) At room temperature, the contact resistance is about 10 ohm-cm/2/, which is low enough to be considered ohmic unless the contact area is very small. Very large scale integration requirements make the ohmic contact for small (micron or sub micron) devices very important.