Ohmic Contacts to P-Type Semiconductors
Original Publication Date: 1982-Jan-01
Included in the Prior Art Database: 2005-Feb-08
The use of p-GaSb provides ohmic contacts to p-type semiconductors. The essence of this technique lies in utilizing the unique property of GaSb, i.e., at its interface with a metal, the fermi level is pinned close to energy, resulting in an accumulation of holes. Transport of carriers across the interface, consequently, shows an ohmic behavior. To provide ohmic contacts to other p-type semiconductors requires a transition layer where the compositions are graded to GaSb from whatever semiconductors are of interest. The drawing shows the configuration for making ohmic contact to p-type GaAs, for example. The graded layer in this case is made of GaSb(1-x) As(x) , with x varying from 0 to 1 at the GaAs interface. To contrast the situation, the configuration of making ohmic contacts to n-GaAs with n-InAs is also shown.