Fabrication of high dielectric constant and low leakage current metal oxide semiconductor capacitor structure

• Main Authors: WU, TSUNG-SHIN, LEE, MING-KWEI, HUANG, JUNG-JIE
• Format: Patent
• Language: Chinese; English
• Published: 01.06.2006
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

The dielectric constant of poly-crystalline titanium oxide (TiO2) films grown on silicon (Si) by metal organic chemical vapor deposition (MOCVD) is high. The leakage current is also high, which is dominated by the grain boundary and lower barrier height. Silicon oxide (SiO2) film is used as an interfacial layer for the structure of MOCVD-TiO2/SiO2/Si. The leakage current is much improved due to the high quality and high barrier height of SiO2/Si, but the total capacitance is lost due to the series of low-dielectric constant SiO2 films and amorphous low dielectric constant of TiO2 film grown on SiO2. Liquid-phase-deposited SiO2 is used as a cap layer for the structure of LPD-SiO2/MOCVD-TiO2/Si, the high dielectric constant of MOCVD-TiO2/Si is preserved. The leakage current is much improved due to the high barrier height SiO2 and the passivation of the dangling bonds of the grain boundary of poly-crystalline MOCVD-TiO2 films by the F from LPD-SiO2 films. Therefore, high dielectric constant and low leakage curre