摘要 |
<p>STATIC RAM CELL Peter Cheng-Yu Chen Alex Au A static RAM cell (11) is constructed utilizing low resistivity positive and negative power supply leads (13,14), thus eliminating the problem of instability of the data stored within the cell. The negative power supply lead is formed of a first layer of low resistivity polycrystalline silicon/tantalum silicide, and the positive power supply lead is formed of a second layer of polycrystalline silicon. By the use of a low resistivity negative power supply lead, the voltage drop on the negative power supply lead is substantially reduced as compared with prior art devices, thereby providing during the read operation substantially equal voltages to the gates of the two bistable transistors of each cell, thus eliminating the problem of instability during reading. Depletion load devices (11,12) are formed utilizing the layer of polycrystalline silicon as the source, drain and channel and the layer of polycrystalline silicon/ tantalum silicide as the gate. In this manner, silicon area is not required to form the depletion load devices, thus minimizing cell size.</p> |