Three-dimensional memory devices

Three-dimensional memory devices using BR as a substrate were demonstrated. A schematic diagram of the optical system used to write, read, and erase information within a cuvette containing the protein is shown in Figure 135.7. The resting state (bR) is assigned to bit 0, and P and Q are assigned to bit 1 (bit 0 should not be confused with the O state) ... 

BR-based memory devices are primarily based on M-state or O-state photochemistry. Holographic devices are based on the blue-shifted M state, although a Q-state-based holography will be discussed. In three-dimensional memories, the write process is particularly dependent on O-state photochemistry. 

In any real memory device the capacitors take up most of the chip area the transistors and resistors are very small. Therefore the FRAM roadmap [8] shown in Table 2 mandates a fully three-dimensional (3D) capacitor structure in the industry by 2008. The state of the art at present is a PZT-lined trench, a Tokyo Institute of Technology-Samsung collaboration that achieves a 6.5 1 aspect ratio for the trenches. Ru electrodes are used, prepared from the organic precursor Ru-DER, from Tosoh Corp. 

MOSFETs. The metal-oxide-semiconductor field effect transistor (MOSFET or MOS transistor) (8) is the most important device for very-large-scale integrated circuits, and it is used extensively in memories and microprocessors. MOSFETs consume little power and can be scaled down readily. The process technology for MOSFETs is typically less complex than that for bipolar devices. Figure 12 shows a three-dimensional view of an n-channel MOS (NMOS) transistor and a schematic cross section. The device can be viewed as two p-n junctions separated by a MOS capacitor that consists of a p-type semiconductor with an oxide film and a metal film on top of the oxide. 

Recently, especially since the LLP phenomenon in SrAl204 Eu, Dy was reported in 1996 [1], LLP materials have been extensively investigated due to its potential application in display in the dark, energy storage, enhancement of the conversion efficiency of solar cell and the fabrication of re-writable three-dimensional optical memory devices, etc [2-5],... 

Lee KW, Nakamura T, One T, Yamada Y, Mizukusa T, Hasimoto H, Park KT, Kurino H, Koyanagi M. Three dimensional shared memory fabricated using wafer stacking technology. Digest of International Electron Device Meeting 2000. p 165-168. 

Nonvolatile FeRAM devices ntilize either PZT or SET derivatives. In low density memory FeRAM prodncts, CSD is frequently nsed as the deposition method. For high-density 4- or 32-Mbit FeRAM prototypes, CSD is still used by industry to fabricate ferroelectric PZT thin-fihn capacitors, although gas phase methods like MOCVD have advantages due to the potential for conformal coverage of small three-dimensional strnctures. 

K. W. Lee, T. Nakamura, T. Ono, Y. Yamada, T. Mizukusa, H. Hashmoto, K. T. Park, H. Kurino, M. Koyanagi. Three-dimensional shared memory fabricated using wafer stacking technology. In Proc. Int l Electronic Device Meeting, 2000, pp. 165 - 168. 

Fulfilling multilayer and miniature structures of memory devices led to the introduction of new materials and sfrucfures. For the structure, the design rule decreases less than 70 nm and the short channel effect (SCE) phenomenon appears to have a bad influence on fhe device drive if exisf-ing planar transistor (TR) is applied. To solve this problem, studies are in progress to apply recessed charmel array TR and three-dimensional structured FinFET in DRAM and floating gate, twin SONOS, and FinFET SONOS in flash memory (Eigure 6.3). 

There are several process requirements for the preparation of polypropylene staple with permanent three-dimensional helical curvature. Specifically, a rectangular spinneret-pack assembly is used to produce flow perturbation and to impart high internal stress. A specially designed cooling device cools the fiber quickly to form a paracrystalline structure in the fiber. The process principle is that the flow perturbed in the polypropylene melt creates internal stress on one side of the fiber section. Because of the stress memory of polypropylene, the internal stress difference at the interface of streamlined and perturbed flows can sustain in the fiber after it has been cooled and solidified. This leads to different crystal structures and shrink properties, and thus a fiber in the shape of a three-dimensional helix. 

Memory cube, a three-dimensional module consisting of stacked memory devices such as DRAMs or SRAMs. 

Three-Dimensional Bacteriorhodopsin-Based Memory Devices... 

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