Frequency response of the current multiplication process in MIS tunnel diodes

In contrast to thick insulator structures, metal-insulator-semiconductor (MIS) diodes with very thin insulating regions (<30 Å for the metal-silicon dioxide-silicon system) allow appreciable tunnel current flow between the metal and the semiconductor. Under such conditions, it has recently been shown that multiplication of minority carriers supplied to the contact region can be obtained if the work function of the metal contact is suitably chosen. This paper reports the first quantitative experimental measurements of this multiplication process and its frequency dependence. Gains in the range 100-1000 are reported for AlSiO ₂Si devices but the frequency response of the gain mechanism for these devices is found to be relatively restricted, measured values being in the 10 kHz range.