Capacitive Load FET Static RAM in Trench Technology
Original Publication Date: 1986-Jan-01
Included in the Prior Art Database: 2005-Mar-08
A capacitive load field-effect transistor (FET) static random-access memory (RAM) in isolation trench technology is made less sensitive to a-particle disturbance during standby by the use of a trench sidewall capacitor determined by diffusion depth contiguous to the sides of the sidewalls. Six devices comprising a resistive load FET static RAM or a four- device quasi-static RAM (without resistive load) are very sensitive to a-particle disturbance during standby condition. This is due to the small standby current (in the nanoampere range) in the resistive load static RAM case, or the absence of current in the quasi-static RAM case. A capacitive load FET static RAM in trench technology provides fast read/write operation and eliminates a-particle sensitivity when provided with the trench sidewall capacitor C1 shown in the figure.