subject: 100 times faster transistor speed carbon new development beyond the amorphous silicon-RFID, semiconductor components, carbon transistor - printing [print this page] 100 times faster transistor speed carbon new development beyond the amorphous silicon-RFID, semiconductor components, carbon transistor - printing
At room temperature semiconductor device manufacturing technology, such as electronic bulletin board will (electronicbillboards) that large-scale applications, and the RFID tags can be disposable ultra-low-cost applications such as possible. But most of the room temperature electron mobility transistors is very low, numerical only one per cent per volt sec cm ^ (cm2/Vs).
Now, Georgia Institute of Technology (Georgia Institute ofTechnology, Georgia Tech) researchers claim that through the use of carbon-60 (C60) film is Buck ball (buckyballs) or fullerenes (fullerenes) to make transistors (transistor) channel (channel), found a ratio of amorphous silicon can be produced (amorphous) at room temperature to 100 times faster transistor manufacturing methods.
"We do not claim to be the first to manufacture in the C60 transistors at room temperature laboratory," GeorgiaTech professor BernardKippelen said: "The innovation of our R & D results is to prove that the process at room temperature and obtained a 3 ~ 5cm2 / Vs such a high electron mobility, but also can get a good renewable (reproducibility), stability, low threshold voltage, and high switching current ratio (on-offcurrent ratios). "
Global research laboratory at room temperature in process technology to take advantage of cheap, high-yield disaster Yao sword? Oll-to-roll) printing or inkjet printing technology to create large displays and low-cost applications such as RFID products ; this way, you do not need those expensive clean room, high-temperature processing process. But there are many ways is trying to use organic materials in the transistors, but also tried to use the formula to find new materials to enhance electron mobility in the channel.
Other research units have achieved higher than the study group GeorgiaTech electron mobility, but mostly through the high temperature process to? Made with transistors. Although the U.S. industry has developed a Kovio inorganic silicon ink (inorganicsiliconink), can be manufactured by means of inkjet printing thin film transistors, but? Process temperature is much higher than the plastic substrate could afford.
Despite GeorgiaTech R & D results, failure to achieve high-temperature process can achieve the electron mobility (Kovio claims that its electron mobility and polysilicon as good), they achieve the electron mobility than amorphous silicon has been. The potential applications of the technology as a means of production requires only 16ms refresh rate (refreshrate) the service displays (service display); they can use low-cost plastic substrates.
Design improvements over the past few years, based, Kippelen says his research team has identified the need for low temperature high electron mobility to optimize the materials and parameters: "Our research is based on organic semiconductors refining (purification) and treatment based on several years of experience. while the gate dielectric (gatedielectric) and the choice of electrode metal, but also play an important role. "
Georgia Tech Professor Bernard Kippelen (middle) at room temperature on transistor research and development projects, and research scientist with the school BenoitDomercq and Xiao-Hong Zhang, a doctoral candidate to work together.
The sake of convenience, GeorgiaTech team model component is manufactured in the silicon substrate; but the researchers claimed that their use of organic transistors C60 all the elements are made at room temperature. Transistors used for the metal electrode at room temperature, it is used with the OLED and plastics used in transparent solar cells? Way (transparentprocess) deposition made the same technology.
"Our electrode is the use of masks (shadow masking) and thermal evaporation (thermalevaporation) process, in the top made of organic semiconductors;" Kippelen said: "Through the metal source (source) and between the substrate to keep enough distance (3 feet), allows the substrate not be deemed as the deposition process overheating. "
Next, researchers will explore the manufacture of n-channel and p-channel transistor means, to take advantage of room temperature organic materials, manufacturing active matrix display for CMOS inverters (inverters), ring oscillator (ringoscillator), logic gate and the auxiliary drive circuit and the like. "Replace the silicon with plastic floor boards, but also our future research project part;" Kippelen said.
However, manufacturing transistor channel using C60 or a disadvantage exists, that is, they are sensitive to oxygen, means that the components must work in an environment in nitrogen. The researchers are planning to re-form a fullerene molecule, and in the way of vacuum packaging components to address the issue.
