As mentioned previously, the production of oxygen atoms and ozone
causes organic impurities on the silicon to be oxidized.
OTS and other silanes such as dodecyltrichlorosilane are used in the
semiconductor industry to form nanofilm SAMs on silicon dioxide substrates during fabrication of integrated circuits. More specifically, these
molecules act as thin insulating gates in metal–insulator semiconductors.
OTS is also used in conjunction with conducting polymers in organicsubstrate LCD displays.
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
*
*
*
*
*
*
*
*
O
O
O
O
O
O
O
O
O
O
HO
HO
HO
HO
OH
OH
HO
HO
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
OH
OH
OH
–H 2 O
HO
Si
Si
Si
Si
Si
Si
Si
Si
Si
Si
Si
Si
Si
Si
Si
Si
Si
Si
Si
Si
Si
Si
– OH or H + /H 2 O
EtOH
O
O
O
OH
Si
+
Hydrolysis
Condensation
Silica network
Figure 10.19 The sol-gel process. Silanes are highly reactive to OH groups and
(R-O) 3 Si–OH molecules and can self-react in a condensation process leading to the
silica network containing nanopores.
CHAPTER 10: Fabrication, Properties, and Applications of Thin Films
410