Nano crystals doped better conductors

'Doped nanocrystals' was developed by researchers, working at Hebrew University, in Jerusalem, Israel, this is the result of research in the field of enhancing the electrical conductivity of sold nanocrystals. guide.

Researchers at Hebrew University, in Jerusalem, Israel, have achieved a breakthrough in the field of nanoscience research, which has succeeded in changing the nanocrystal properties with impurity atoms, through a process called doping. This paved the way for the production of semiconductor nanocrystals that were enhanced with electrical conductivity.

Semiconductor nanocrystals consist of tens to thousands of atoms and are about 10,000 times smaller than the width of a human hair. These small crystalline particles are used in a wide range of fields, such as: Solid lighting techniques, solar cells and biological images. One of the main potential uses of these special materials is in the semiconductor industry, which focuses on the reduction of special materials, which has been going on for 50 years and is now Now, the size of the miniature object lies within the nanometer threshold.

However, semiconductors are poor conductors of electricity, and to use them in electronic circuits, their electrical conductivity must be adjusted by adding impurities. In this process, the outer atoms, called impurities, are mixed into semiconductors, creating an improvement that increases its electrical conductivity.

Today, the annual semiconductor industry spends billions of dollars, in an effort to deliberately add impurities to semiconductor products, which is an important step in the production of many electronic products, including : computer chips, LED lights and solar cells.

Due to the importance of doping for the semiconductor industry, researchers around the world have made efforts to create doped nanocrystals, with even more microscopic dimensions and also to improve the method of producing electronic devices. Unfortunately, small crystals are resistant to doping, since they are too small in size, causing impurities to spill. Another problem is the lack of available analytical techniques to study a small number of impurities in nanocrystals. Due to these limitations, most of the research in this area has focused on the introduction of magnetic impurities, which can be analyzed more easily. However, magnetic impurities do not really improve the electrical conductivity of nanocrystals.

Professor Uri Banin and his student, David Mocatta, a graduate student, working at the Nanoscience Science & Technology Center, Hebrew University, Israel, has achieved a breakthrough in developing a chemical reaction. Simple, at room temperature to mix metal impurity atoms into semiconductor nanocrystals. They have seen new effects, never reported before. However, when researchers tried to explain the achievements, they realized that I did not understand the physical properties of doped nanocrystals.

Some time later, in collaboration with Professor Oded Millo, worked at Hebrew University, Israel; with Guy Cohen and Professor Eran Rabani, working at Tel Aviv University, Israel; Researchers have built a comprehensive picture of how impurities affect the properties of nanocrystals. The initial difficulties in explaining this process were a precursor to new discoveries, when they discovered that impurities affect nanocrystals in unexpected ways, resulting in crystals. nanons can produce amazing new physical properties.

' We had to use a combination of many techniques, when studying together, to make sure that we managed well the doped nanocrystals. It took five years to achieve these results , 'said David Mocatta.

The results of this study were published in the journal Science , creating a premise for the development phase of many applications of nanocrystals in many fields: from electronics to optics, from sensors to Alternative energy solutions. Doped nanocrystals can be used to make new types of nano lasers, solar cells, sensors and new transistors, or meet stringent industry requirements. Semiconductor.