高速石墨晶体管问世
文章来源:未知 文章作者:meng 发布时间:2010-09-06 06:24 字体: [ ]  进入论坛
(单词翻译:双击或拖选)

Graphene(石墨烯,单层石墨) , a one-atom-thick layer of graphitic carbon, has great potential to make electronic devices such as radios, computers and phones faster and smaller. But its unique properties have also led to difficulties in integrating the material into such devices. In a paper published Sept. 1 in the journal Nature, a group of UCLA researchers demonstrate how they have overcome some of these difficulties to fabricate(制造,装配) the fastest graphene transistor1 to date(至今) .

With the highest known carrier mobility2 — the speed at which electronic information is transmitted by a material — graphene is a good candidate for high-speed radio-frequency electronics. But traditional techniques for fabricating the material often lead to deteriorations(恶化,退化) in device quality.

The UCLA team, led by professor of chemistry and biochemistry Xiangfeng Duan, has developed a new fabrication process for graphene transistors3 using a nanowire as the self-aligned gate.

Self-aligned gates are a key element in modern transistors, which are semiconductor4 devices used to amplify5 and switch electronic signals. Gates are used to switch the transistor between various states, and self-aligned gates were developed to deal with problems of misalignment(不重合,未对准) encountered because of the shrinking scale of electronics.

To develop the new fabrication technique, Duan teamed with two other researchers from the California NanoSystems Institute at UCLA, Yu Huang, an assistant professor of materials science and engineering at the Henry Samueli School of Engineering and Applied7 Sciences, and Kang Wang, a professor of electrical engineering at the Samueli School.

"This new strategy overcomes two limitations previously8 encountered in graphene transistors," Duan said. "First, it doesn't produce any appreciable9 defects in the graphene during fabrication, so the high carrier mobility is retained(保留,保存) . Second, by using a self-aligned approach with a nanowire as the gate, the group was able to overcome alignment6 difficulties previously encountered and fabricate very short-channel devices with unprecedented10 performance."

These advances allowed the team to demonstrate the highest speed graphene transistors to date, with a cutoff frequency(截止频率) up to 300 GHz — comparable to the very best transistors from high-electron mobility materials such gallium arsenide(砷化镓) or indium phosphide(磷化铟) .

"We are very excited about our approach and the results, and we are currently taking additional efforts to scale up the approach and further boost the speed." said Lei Liao, a postdoctoral fellow at UCLA.

High-speed radio-frequency electronics may also find wide applications in microwave communication, imaging and radar11 technologies.



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1 transistor WnFwS     
n.晶体管,晶体管收音机
参考例句:
  • This make of transistor radio is small and beautifully designed.这半导体收音机小巧玲珑。
  • Every transistor has at least three electrodes.每个晶体管至少有三个电极。
2 mobility H6rzu     
n.可动性,变动性,情感不定
参考例句:
  • The difference in regional house prices acts as an obstacle to mobility of labour.不同地区房价的差异阻碍了劳动力的流动。
  • Mobility is very important in guerrilla warfare.机动性在游击战中至关重要。
3 transistors ff750796e6ff1fb40d6a8248a6485dc3     
晶体管( transistor的名词复数 ); 晶体管收音机,半导体收音机
参考例句:
  • In semiconductor receivers transistors take the place of vacuum tubes. 在半导体收音机中晶体管代替了真空管。
  • We often turn to this handbook for information on transistors. 我们常从这本手册查阅有关晶体管的资料。
4 semiconductor Uzuwq     
n.半导体
参考例句:
  • In the beginning,engineers hoped to use semiconductor lasers.在开始时,工程师们希望能够利用半导体激光器。
  • The main agent of the company brand semiconductor sales.本公司主要代理各品牌半导体销售。
5 amplify iwGzw     
vt.放大,增强;详述,详加解说
参考例句:
  • The new manager wants to amplify the company.新经理想要扩大公司。
  • Please amplify your remarks by giving us some examples.请举例详述你的话。
6 alignment LK8yZ     
n.队列;结盟,联合
参考例句:
  • The church should have no political alignment.教会不应与政治结盟。
  • Britain formed a close alignment with Egypt in the last century.英国在上个世纪与埃及结成了紧密的联盟。
7 applied Tz2zXA     
adj.应用的;v.应用,适用
参考例句:
  • She plans to take a course in applied linguistics.她打算学习应用语言学课程。
  • This cream is best applied to the face at night.这种乳霜最好晚上擦脸用。
8 previously bkzzzC     
adv.以前,先前(地)
参考例句:
  • The bicycle tyre blew out at a previously damaged point.自行车胎在以前损坏过的地方又爆开了。
  • Let me digress for a moment and explain what had happened previously.让我岔开一会儿,解释原先发生了什么。
9 appreciable KNWz7     
adj.明显的,可见的,可估量的,可觉察的
参考例句:
  • There is no appreciable distinction between the twins.在这对孪生子之间看不出有什么明显的差别。
  • We bought an appreciable piece of property.我们买下的资产有增值的潜力。
10 unprecedented 7gSyJ     
adj.无前例的,新奇的
参考例句:
  • The air crash caused an unprecedented number of deaths.这次空难的死亡人数是空前的。
  • A flood of this sort is really unprecedented.这样大的洪水真是十年九不遇。
11 radar kTUxx     
n.雷达,无线电探测器
参考例句:
  • They are following the flight of an aircraft by radar.他们正在用雷达追踪一架飞机的飞行。
  • Enemy ships were detected on the radar.敌舰的影像已显现在雷达上。
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