| 摘要 |
A memory system that includes a dynamic random access memory (DRAM) cell that includes an access transistor and a storage capacitor. The storage capacitor of the DRAM cell is fabricated by forming a polysilicon crown electrode, a dielectric layer overlying the polysilicon crown, and a polysilicon plate electrode overlying the dielectric layer. A first set of thermal cycles are performed during the formation of the storage capacitor to form and anneal the elements of the capacitor structure. After the first set of thermal cycles are complete, shallow P+ and/or N+ regions are formed by ion implantation, and metal salicide is formed. As a result, the relatively high first set of thermal cycles required to form the capacitor structure does not adversely affect the shallow P+ and N+ regions or the metal salicide. A second set of thermal cycles, which are comparable to or less than the first set of thermal cycles, are performed during the formation of the shallow regions and the metal salicide. The DRAM cell is operated in response to a word line driver that is controlled to provide a positive boosted voltage and a negative boosted voltage to the word line, thereby controlling access to the DRAM cell. The positive boosted voltage is greater than Vdd but less than Vdd plus the absolute value of a transistor threshold voltage Vt. Similarly, the negative boosted voltage generator is less than VSS by an amount less than Vt.
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