Innovative Progress in Electronic Thin Films

(1) The silicon film is made of liquid materials.

On April 6, 2006, the research team led by Tatsuya Shibata, a researcher at the R & D headquarters of Seiko Epson, published the research results in the British journal Nature Science, saying that they successfully made silicon films using liquid materials. The electron mobility of the low-temperature polysilicon thin film field effect transistor using this silicon thin film is as high as 108 cm2 / VS, which achieves the same performance as the thin film field effect transistor formed by the chemical vapor deposition method in the past.

Because of the use of liquid materials, the film has a great feature that it can be formed by coating. It does not need expensive equipment such as vacuum equipment and dust-free operation room. The new thin film field effect transistor is formed by coating by spin plating.

(2) The ultra-thin electromagnetic noise absorbing film has been developed.

In April 2006, Sumitomo Corporation of Japan developed an ultra-thin electromagnetic noise absorption film "ultra-thin noise suppression film" for small digital devices such as mobile phones and digital cameras. It can absorb the electromagnetic noise found in the stages of combined module components and mass production trial production of final products. Since the overall thickness of the suppression film including the adhesive is controlled at 0.08 mm, it is suitable for portable high-performance equipment.

The product adopts the structure of filling the ultra-thin and soft resin layer with a high density of magnetic filler and coating the acrylic adhesive layer by layer. It can absorb 10m ~ 3GHz wide range electromagnetic noise and convert it into tiny heat, so as to ensure the quality of signal transmission through the flexible circuit board.

Digital equipment is tending to be modular in design, and each module component requires optimization including electromagnetic noise. However, when several module components are combined to form the final product, sometimes unexpected electromagnetic noise will be generated at the design stage. In this case, an electromagnetic noise absorbing sheet is used. This new type of electromagnetic noise absorber, with ultra-thin as its selling point, is expected to be in great demand in the field of ultra-small, ultra-thin, multi-functional, high-performance, high-density design equipment.

(3) Indium arsenide two-dimensional semiconductor quantum film was developed.

In January 2011, the research team led by Ali Javey of the University of California, Berkeley, published a paper in Nano Express that they developed a new two-dimensional semiconductor, which is a "quantum film" made of indium arsenide, with a ribbon structure, and can be transformed from a blocky three-dimensional material to a two-dimensional material simply by reducing the size.

When the size of semiconductor materials is as small as nanometer, their electrical and optical properties will change greatly, resulting in quantum confinement effect. Thus, people can manufacture two-dimensional transistors called quantum films. The quantum film is about 10 nanometers or less, and its operation is basically limited to a two-dimensional space. Because of this unique property, they can display their strong points in the highly specialized field of quantum optics and electronics applications.

At present, graphene materials are mostly used in the research of two-dimensional semiconductors. Javi's research team has created a "quantum film" of indium arsenide through another way. Moreover, the new quantum film can be used as an independent material without a substrate and can be combined with various substrates, while other similar materials can only be used for one substrate in the past.

They first grow indium arsenide on gallium antimonide and aluminum gallium antimonide substrates, put it on the top layer, and design it into any desired shape, then etch the bottom layer, and move the remaining indium arsenide layer to any required substrate to make the final product.