Preparation and Characterization of Ultralow-Dielectric-Constant Porous SiCOH Thin Films Using 1,2-Bis(triethoxysilyl)ethane, Triethoxymethylsilane, and a Copolymer Template

Abstract

Ultralow-dielectric-constant (k) porous SiCOH films have been prepared using 1,2-bis(triethoxysilyl)ethane, triethoxymethylsilane, and a poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) triblock copolymer template by means of spin-coating. The resulting films were characterized by cross-section scanning electron microscopy, small-angle x-ray diffraction, atomic force microscopy, Fourier-transform infrared spectroscopy, nanomechanical testing, and electrical measurements. Thermal treatment at 350°C for 2 h resulted in the formation of ultralow-k films with k of $2.0, leakage current density of 3 9 10 À8 A/cm 2 at 1 MV/cm, reduced modulus (E r ) of $4.05 GPa, and hardness (H) of $0.32 GPa. After annealing between 400°C and 500°C for 30 min, the resulting films showed fluctuant k values of 1.85 to 2.22 and leakage current densities of 3.7 9 10 À7 A/cm 2 to 3 9 10 À8 A/cm 2 at 0.8 MV/cm, likely due to the change of the film microstructure. Compared with 350°C annealing, higher-temperature annealing can improve the mechanical strength of the ultralow-k film, i.e., E r % 5 GPa and H % 0.56 GPa after 500°C annealing.

Enhanced Thermal Stability of Low-k Ethyl-Bridged Organosilicas Using Laser Spike Annealing

“…Thin films of ethyl-bridged organosilane low- k dielectrics on nominally undoped bare Si substrates (native oxide) were prepared by using a sol–gel process. ,,, The silane precursor 1,2-bis­(triethoxy­silyl)­ethane (BTESE) and a commercial porogen (Brij-76) were obtained from Sigma-Aldrich. The BTESE and porogen were dissolved separately in 2-methoxy-1-propanol (PMOH) to 25 wt % concentrations.…”

Characterization of PECVD ultralow dielectric constant porous SiOCH films using triethoxymethylsilane precursor and cinene porogen

“…Figure 2 shows the FTIR spectra of the as-deposited film and those annealed at different temperatures. In terms of the asdeposited film, the absorption peak between 2800-3000 cm −1 corresponds to the CH x group [16,19], and the strongest absorption band between 950 cm −1 and 1250 cm −1 should be associated with the Si-O-Si (around 1055 cm −1 ) and Si-O-C (around 1135 cm −1 ) configurations [17,19], which contributes a lot to the framework of the porous film. Furthermore, the absorption peak at 1270 cm −1 originates from the symmetrical deformation vibration of -CH 3 in Si-CH 3 , and the peaks between 780 cm −1 and 850 cm −1 correspond to the C-H rocking vibration in Si-CH 3 [17,19].…”

“…Undoubtedly, an increased degree of cross-linking can improve the mechanical performance of the film [25]. Figure 7 shows the C1s spectra for different SiOCH films, each of which can be well divided into three Gaussian peaks, assigned to C-Si (283.9 ± 0.1 eV), C-C/C-H (284.9 ± 0.1 eV) and C-O (286.2 ± 0.1 eV) bonds, respectively [16,17]. As the MFRR of LIMO/MTES increased from 1.0 to 2.0, the relative area percentage of the C-Si peak increased from 18% to 22%, and that of the C-C/C-H peak also increased from 42% to 47%.…”

Preparation and Characterization of SiCOH Film Using a New Precursor Trimethoxy [2-(oxabicyclo [4.1.0] hept-3yl) Ethyl] Silicane

“…As one of low-k materials, the SiCOH films have been intensively investigated via plasma enhanced chemical vapor deposited (PECVD) and spin-coating [1][2][3]. This is ascribed to some advantages for the SiCOH films [4], i.e. the chemical bonds of C-C, C-Si, and C-H incorporated into the film can reduced the dielectric constant compared to the Si-O bonds and it can be Strengthen the mechanical properties and so on.…”

“…In terms of spin-coated SiCOH films, various precursors have been explored such as BTEE, MTES and TEOS. [4][5][6][7]. Further, to achieve ultra-low k films, some porogens such as P123 and CTAB are introduced initially into the solution, and then removed by post-annealing the coated film.…”