porous SiO2

• Main Authors: Chih-Hao Wang, 王致皓
• Other Authors: Fon-Shan Huang
• Format: Others
• Language: zh-TW
• Published: 1999
• Online Access: http://ndltd.ncl.edu.tw/handle/18372150403206315560

碩士 === 國立清華大學 === 電子工程研究所 === 87 === The porous SiO2 films were fabricated by sol-gel method. The various ratio of C2H5OH, H2O, HCl, NH4OH to TEOS were prepared. Spin-coating, aging, drying and thermal treatment were applied. After the porous SiO2 films were formed, ellipsometer, Rutherford backscattering spectrometer ( RBS ), BOE etchant, C-V measurement, Auger electron spectrometer ( AES ), I-V measurement, Fourier transform infrared spectrometer ( FTIR ), transmission electron microscope ( TEM ), and scanning electron microscope ( SEM ) were employed to study the refractive index, density, porosity, etching rate, dielectric constant, thermal stability, breakdown electric filed, chemical bond, pore size, and planarization of porous SiO2 films. From above measurements, we found that the refractive index, density and dielectric constant rise with the ratio of H2O/TEOS. The porosity behaviors opposite. The etching rate with BOE etchant would increase with the ratio of C2H5OH /TEOS. In the aspect of chemical bond, -OH bond and bond including C would increase with the increasing of H2O and C2H5OH respectively. The electric breakdown field has tendency to rise with the increasing of porosity. For thermal stability study, TiN with thickness ~600A can succeed in obstructing the diffusion of Cu into the porous SiO2 at 400℃ sintering process. In this thesis, the porosity of porous SiO2 as high as 45% can be obtained. The pore size was approximately about 20nm or less. The dielectric constant of the film can be reduced to 2.6. The planarization of spin-coating process was also under control.