首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   19篇
  免费   13篇
化学   9篇
综合类   1篇
物理学   22篇
  2023年   1篇
  2021年   1篇
  2019年   2篇
  2018年   1篇
  2017年   1篇
  2016年   1篇
  2015年   1篇
  2014年   1篇
  2013年   7篇
  2012年   2篇
  2011年   2篇
  2010年   2篇
  2008年   1篇
  2007年   1篇
  2006年   1篇
  2005年   2篇
  2004年   3篇
  2001年   1篇
  1999年   1篇
排序方式: 共有32条查询结果,搜索用时 218 毫秒
21.
Based on the charge storage mode,it is important to investigate the scaling dependence of memory performance in silicon nanocrystal(Si-NC) nonvolatile memory(NVM) devices for its scaling down limit.In this work,we made eight kinds of test key cells with different gate widths and lengths by 0.13-μm node complementary metal oxide semiconductor(CMOS) technology.It is found that the memory windows of eight kinds of test key cells are almost the same of about1.64 V @ ±7 V/1 ms,which are independent of the gate area,but mainly determined by the average size(12 nm) and areal density(1.8×10~(11)/cm~2) of Si-NCs.The program/erase(P/E) speed characteristics are almost independent of gate widths and lengths.However,the erase speed is faster than the program speed of test key cells,which is due to the different charging behaviors between electrons and holes during the operation processes.Furthermore,the data retention characteristic is also independent of the gate area.Our findings are useful for further scaling down of Si-NC NVM devices to improve the performance and on-chip integration.  相似文献   
22.
王利  孙红芳  周惠华  朱静 《中国物理 B》2010,19(10):108102-108102
A method of fabricating Cu nanocrystals embedded in SiO2 dielectric film for nonvolatile memory applications by magnetron sputtering is introduced in this paper. The average size and distribution density of Cu nanocrystal grains are controlled by adjusting experimental parameters. The relationship between nanocrystal floating gate micro-structure and its charge storage capability is also discussed theoretically.  相似文献   
23.
掺杂对铌酸锂晶体非挥发全息存储性能的影响   总被引:1,自引:0,他引:1       下载免费PDF全文
通过研究掺镁、掺锌和掺铟同成分铌酸锂晶体的紫外-红光双色全息存储性能,发现双色记录响应时间均比单色记录时明显缩短,最多的可减小3个数量级;双色记录灵敏度大幅度提高,在掺镁5 mol.%的晶体中可达到11 cm/J.在掺杂浓度超过抗光损伤阈值的铌酸锂晶体中,均可实现非挥发全息存储.但是,在掺镁、锌样品中,深、浅能级中心上的光栅反相,而在掺铟样品中则表现为同相.这是由于掺杂离子的种类不同,在铌酸锂晶体中形成的缺陷中心也不同所引起的. 关键词: 掺杂 铌酸锂晶体 非挥发 全息存储  相似文献   
24.
根据双中心带输运模型,对(Ce,Cu):LiNbO3晶体双中心非挥发全息记录进行了理论研究与优化。推导了(Ce,Cu):LiNbO3晶体的微观参量,采用数值方法通过严格求解模拟双中心带输运方程来模拟全息记录过程。分析了记录过程中,记录与敏化光强、Ce和Cu掺杂浓度以及晶体微观参量对(Ce,Cu):LiNbO3晶体双中心全息记录的影响。发现(Ce,Cu):LiNbO3晶体非挥发全息记录中实现高衍射效率与固定效率的主导因素是深中心Cu,在记录过程中,深中心Cu建立起了很强的空间电荷场。数值模拟的结果经过实验验证,最高饱和与固定衍射效率别为60.5%和53.8%。  相似文献   
25.
A new approach on usage of S‐1‐dodecyl‐S′‐(α,α′‐dimethyl‐α″‐acetic acid)trithiocarbonate (DDAT)‐covalently functionalized graphene oxide (GO) as reversible addition fragmentation chain transfer (RAFT) agent for growing of poly(N‐vinylcarbazole) (PVK) directly from the surface of GO was described. The PVK polymer covalently grafted onto GO has Mn of 8.05 × 103, and a polydispersity of 1.43. The resulting material PVK‐GO shows a good solubility in organic solvents when compared to GO, and a significant energy bandgap of ~2.49 eV. Bistable electrical switching and nonvolatile rewritable memory effect, with a turn‐on voltage of about ?1.7 V and an ON/OFF state current ratio in excess of 103, are demonstrated in the Al/PVK‐GO/ITO structure. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011  相似文献   
26.
27.
Fluorene based donor‐acceptor polyimides, including poly[bis‐(4‐aminophenyl)fluorene‐hexanediamide] [PA(BAP F‐AC)], poly[bis‐(4‐aminophenyl)fluorene‐hexafluoroisopropylidenediphthalimide] [PI(BAPF‐6FDA)], poly[bis‐(4‐aminophenyl)fluorene‐oxydiphthalimide] [PI(BAPF‐ODPA)], and poly[bis‐(4‐aminophenyl)fluorene‐1,2,4,5‐cyclohexanetetracarboxylic diimide] [PI(BAPF‐HPMDA)], as charge storage layer (electret) are employed for nonvolatile memory device applications. The polyimides are consisted of electron‐donating fluorene diamine moiety (BAPF) and neutral (AC and HPMDA) or electron‐accepting (6FDA and ODPA) moieties, respectively. The memory characteristics of these devices can be tuned from the EORM (erase once and read many times) behavior [PA(BAPF‐AC)], semi‐flash [PI(BAPF‐ODPA)], [PI(BAPF‐HPMDA)], to a flash type memory [PI(BAPF‐6FDA)]. The PI(BAPF‐6FDA) devices show the largest memory window of 77 V and a long retention time over 104 s with a high Ion/Ioff current ratio of 108. This is attributed to the largest torsion angle of PI(BAPF‐6FDA) stabilizing charge transfer (CT) complexes. The write‐read‐erase‐read cycles were stably operated over 100 cycles. This work provides a new insight into the relationship between the CT effect and the nonvolatile memory behavior. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 602–614  相似文献   
28.
Wen Xiong 《中国物理 B》2023,32(1):18503-018503
Amorphous In-Ga-Zn-O (a-IGZO) thin-film transistor (TFT) memories with novel p-SnO/n-SnO2 heterojunction charge trapping stacks (CTSs) are investigated comparatively under a maximum fabrication temperature of 280 ℃. Compared to a single p-SnO or n-SnO2 charge trapping layer (CTL), the heterojunction CTSs can achieve electrically programmable and erasable characteristics as well as good data retention. Of the two CTSs, the tunneling layer/p-SnO/n-SnO2/blocking layer architecture demonstrates much higher program efficiency, more robust data retention, and comparably superior erase characteristics. The resulting memory window is as large as 6.66 V after programming at 13 V/1 ms and erasing at -8 V/1 ms, and the ten-year memory window is extrapolated to be 4.41 V. This is attributed to shallow traps in p-SnO and deep traps in n-SnO2, and the formation of a built-in electric field in the heterojunction.  相似文献   
29.
Qianmin Dong  Liren Liu  De'an Liu  Cuixia Dai   《Optik》2004,115(9):427-431
Grating spacing dependence of nonvolatile holographic recording in doubly doped lithium niobate crystals is theoretically investigated allowing arbitrary charge transport lengths. It is shown that the nonvolatile refractive index modulation initially increases with increasing grating spacing, then a saturation behavior arises because of the dominant bulk photovoltaic effect. Although different charge transport length results in different nonvolatile refractive index modulation, the grating spacing dependence of nonvolatile holographic recording obeys almost the same rules for arbitrary charge transport lengths. The experimental results obtained by recording nonvolatile holograms in LiNbO3:Cu:Ce crystals with different grating spacing are consistent with the theoretical analyses.  相似文献   
30.
Nonvolatile photorefractive gratings have been recorded in LiNbO3:Cu:Ce crystals by using a He–Ne laser (633 nm) for recording and an argon ion laser (458 nm) for sensitizing. The sensitizing light increases the recording sensitivity by abexp(−Is/c) and saturation behavior will appear with high enough intensity of sensitizing light. The recording light increases the slope of η1/2 as a function of time during the initial stages of hologram formation by sublinear Ixr (x<1) and thus the recording light decreases the recording sensitivity. The dependence of saturation diffraction efficiency on the intensities of the recording and sensitizing light shows that there is a maximum dynamic range of the recording process.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号