Silicon dioxide deposited by using liquid phase deposition at room temperature for nanometer-scaled isolation technology

A selective liquid phase deposition (LPD) of silicon dioxide was performed on a nanometer-scaled photoresist pattern fabricated by using an oxygen-plasma downstream-ashing technique. With the selective LPD method, silicon dioxide can be deposited at low temperatures under 50 degrees C without thermal damage. Using the selective-liquid-phase-deposited silicon-dioxide layer as a wet etching mask, we could fabricate 600-nm-scale isolated structures. The LPD silicon dioxide showed excellent step coverage and good surface morphology. Moreover, the maximum capacitance value of the LPD silicon dioxide was 7 pF. The leakage current density of the LPD silicon dioxide was also very low, which indicated that the LPD silicon dioxide was a good insulating material for integrated circuit (IC). These results raise possibilities of fabricating new types of nanometer-scaled trenches and other nanometer-scale silicon-based devices.