In this chapter and Chap. 7, the liquid silicon family of materials (LSFMs) shown in Fig. 4.1 are introduced in detail. In this chapter, three materials, i.e., SiO2, CoSi2, and Al, are introduced as LSFM part-1, while SiC is described in a separated chapter (Chap. 7) as LSFM part-2. This is simply because the contents of SiC are too large to be included in one chapter.
In Sect. 6.1 fabrication of SiO2 as the first example of LSFM is introduced; an SiO2 film with excellent quality can be prepared via oxidation of a polysilane film. After that thin film transistors (TFTs) were fabricated, in which one SiO2 layer (gate insulator/underlayer) of the transistor was formed using solution process. Next the TFTs, in which two SiO2 layers (gate insulator/underlayer) and a channel Si layer were solution processed, are introduced.
In Sect. 6.2, as the second example, formation of a cobalt disilicide (CoSi2) film using CPS and dicobalt octacarbonyl (Co2(CO)8) is introduced. It was demonstrated that a high-quality epitaxial CoSi2 layer was grown on a silicon (100) surface. Its resistivity was as low as 15 μΩcm.
In Sect. 6.3, as the third example, aluminum (Al) metal formation using a liquid precursor ink was described. Of course Al is not Si, but the idea of obtaining solid from a liquid precursor is very similar to that of silicon related materials and Al is one of components needed for a MOS-FET. So I dare to classify this material technology into LSFM. We developed a liquid process for Al metal using triethylamine alane, especially aiming to realize a selective deposition method.