| 摘要 |
A nonvolatile nondestructible read-out ferroelectric FET memory (10, 40, 60, 80, 100, 110, 120, 130, 160) comprising a semiconductor substrate (19), a ferroelectric functional gradient material ("FGM") thin film (26, 50, 70, 90, 20, 140, 170), and a gate electrode (30). In one basic embodiment, the ferroelectric FGM thin film (26, 50, 70, 90, 20, 140, 170) contains a ferroelectric compound and a dielectric compound. The dielectric compound has a lower dielectric constant than the ferroelectric compound. There is a concentration gradient of the ferroelectric compound in the thin film. In a second basic embodiment, the FGM thin film (26, 50, 70, 90, 20, 140, 170) is a functional gradient ferroelectric ("FGF"), in which compositional gradients of ferroelectric compounds result in unconventional hysteresis behavior. The unconventional hysteresis behavior of FGF thin films is related to an enlarged memorywindow in ferroelectric FET memories. FGM thin films (26, 50, 70, 90, 20, 140, 170) are preferably formed using a liquid source MOD methods, preferably a multisource CVD method. |
