Yogesh Mhaisagar | North Maharashtra University (original) (raw)

Uploads

Papers by Yogesh Mhaisagar

Now a day’s thinfilm science and technology play a crucial role for the development of semiconduc... more Now a day’s thinfilm science and technology play a crucial role for the development of semiconductor industry. A better fundamental understanding of materials and deposition techniques leads to incorporate new materials in modern devices. Along with this an introduction of new sophisticated analytical instruments and techniques has been developed to characterize thin films for actual implementation in current technology. The major applications of thin films are in nanoelectronics, communications, sensors and in all kinds of energy generation methods. The present chapter elaborates the working principles of various deposition and characterization techniques. Surface Modification and Electrical Characterization of Porous Low-k Thin Films for Nanoelectronics Applications Mr.Yogesh S. Mhaisagar, Department of Electronics, NMU, Jalgaon (2013) 2.2 CHAPTER-2 THIN FILM DEPOSITION AND CHARACTERIZATION TECHNIQUES 2.

Invertis Journal of Science & Technology, 2016

This paper investigates the effect of different hydrofluoric (HF) acid catalyst concentrations on... more This paper investigates the effect of different hydrofluoric (HF) acid catalyst concentrations on properties of silica aerogel thin films. The silica aerogel thin films were prepared by sol-gel spin on method followed by solvent evacuation from wet gel film under isopropyl alcohol supercritical conditions in autoclave. The refractive index (RI) of silica aerogel thin films observed to be reduced from 1.4 to 1.21 with increase in HF concentration. Based on RI value, porosity percentage and density of films were determined. The highest porosity of 54% and lowest density of 1.03 gm/cm3 is observed for the films deposited using 0.5 ml HF concentration. The calculated dielectric constant of the films deposited at 0.5 ml HF concentration is found to be lowered up to 2.3 for film. The incorporation of F in the film matrix is validated by using FTIR and EDAX. Peak appeared around 930 cm-1 of FTIR spectra shows the incorporation of F ion and forms Si-F bond in the silica matrix structure. Me...

Silicon

Effect of swift heavy ions (SHI) on low-k SiO2 thin films has been investigated. SiO2 thin films ... more Effect of swift heavy ions (SHI) on low-k SiO2 thin films has been investigated. SiO2 thin films were deposited on pre-cleaned p-Si substrate by using sol-gel spin coating technique. Further, deposited films were annealed at 400 ∘C to remove structural irregularities. Prepared samples were irradiated with 200 MeV Ag15+ ions at different ion fluence such as 5 × 1011, 1 × 1012 and 5 × 1012 ions/cm2. Deposition of SiO2 was confirmed by using EDAX and FTIR spectroscopy. Increase in ion fluence increases the RMS roughness from 1.49 to 7.79 nm. The transformation of deposited material from polycrystalline to amorphous nature was confirmed from XRD spectra. Increase in SHI fluence decreases the grain size from 181.3 to 74.1 nm for pristine and sample irradiated at 5 × 1011 ions/cm2. Whereas, for sample irradiated with 5 × 1011 ions/cm2 fluence doesn’t show crystalline peak at (011). It is observed that SHI irradiation leads to grain agglomeration with decrease in crystal size at higher fluence. Further, conductivity of the samples under study was observed to be decreased with increase in ion fluence. Thus, it is demonstrated that the surface and structural properties of low-k silica thin films can be tailored by controlling the SHI fluence.

Silicon, 2016

The present work is focused towards the lowering of the k value of deposited SiO 2 thin films by ... more The present work is focused towards the lowering of the k value of deposited SiO 2 thin films by varying solvent concentration i.e. ethanol in the range 4-10 ml. Porous low-k thin films were synthesized by using the sol-gel spinon technique. A non-ionic surfactant polysorbate 80 (Tween 80) was used as a porogen to generate the porosity in the film matrix. The lower values of refractive index and film density were measured to be 1.19 and 0.94 gm/cm 3 respectively for 10 ml solvent concentration. Further, the lowest k value of 2.2 and highest porosity percentage of 58.5 % were obtained for the same film due to the dilution of coating solution at higher solvent concentration. The water contact angle of the film was observed to be increased to 106.3 • which indicates the transformation of the deposited film surface from hydrophilic to hydrophobic. The change in chemical structure as an effect of solvent concentration is studied by using FTIR. From FTIR spectra the disappearance of Si-OH groups at higher solvent concentration reveals the increase in condensation rate. Overall in this study, the result shows the significant change in structural, chemical and optical properties of the deposited films at 10 ml solvent concentration. Such deposited porous thin films with lower k value and enhanced hydrophobicity can be used as an interlayer dielectric (ILD) for back end of line (BEOL) in CMOS technology.

Porous SiO2 low-k thin films with low dielectric constant were successfully deposited by sol-gel ... more Porous SiO2 low-k thin films with low dielectric constant were successfully deposited by sol-gel spincoating technique. The films were deposited by using Tertaethylorthosilicate (TEOS) as a precursor solution and HF was used as an acid catalyst solution. The Tween80 with different volumetric concentrations i.e. 0.0 ml, 0.5 ml and 0.7 ml was used as a pore generator to lower the dielectric constant of the films by introducing the porosity in the films matrix. The thickness and refractive index (RI) of low-k thin films have been measured by Ellipsometer. The refractive index and thickness of the films observed to be decreasing with increase in Tween80 concentration. The chemical bonding structures of films were analyzed by using Fourier transform infrared spectroscopy (FT-IR) spectroscopy and the stretching, bending and rocking peaks appear at 1077 cm-1 , 967 cm-1 , 447 cm-1 respectively confirm the formation of Si-O-Si network. The RIs of the films deposited at 0 ml, 0.5 ml and at 0.7 ml of Tween80 concentration are found to be 1.34, 1.26, and 1.20 respectively. Based on RI values of the films, the porosity percentage, density and dielectric constant have been calculated by standard formulation method. The increase in porosity percentage of films from 3 % to 55 % with increase in Tween80 concentration reveals that, the most of the hydroxyl group and porogen get evaporated and form more voids in the films. This increase in porosity percentage causes to lower the dielectric constant of films and was found to be 2.26 at the 0.7 ml of Tween80 concentration. Such porogen based low dialectic constant thin films can be suitable for interlayer dielectric (ILD) applications in ULSI circuits.

The low-k thi n films ha ve been d eposited s ucc essfully by sol gel t echni qu e usi n g tetrae... more The low-k thi n films ha ve been d eposited s ucc essfully by sol gel t echni qu e usi n g tetraethylorthosilicate (TEOS) precursor and the surface of deposited thin films have been modified by wet chemical treatment using trimethylcholorsilane (TMCS) and hexane solution with 15 % volume ratio to remove the hydroxyl groups from the surface of deposited low-k thin films. The characterization of the as deposited and surface modified low-k thin films has been carried out by Ellipsometer, Fourier t r a n s f o r m i n f r a r e d (F T I R) s p e c t r o m e t e r , a n d c o n t a c t a n g l e m e t e r . F o r t h e determination of the dielectric constant of the deposited thin film the metal – insulator-semiconductor (MIS) structure was formed by depositing the Aluminium (Al) metal on the low-k thin film. Further the capacitance-voltage curve of the MIS structure has been obtained at 1 MHz frequency. The dielectric constant of the as deposited thin film is found to be 2.15. The lower...

16th International Workshop on Physics of Semiconductor Devices, 2012

Physics of Semiconductor Devices, 2013

Microelectronic Engineering, 2014

ABSTRACT The surface modification of sol–gel deposited low-k thin films has been carried out succ... more ABSTRACT The surface modification of sol–gel deposited low-k thin films has been carried out successfully by trimethylchlorosilane (TMCS) using wet chemical treatment method. Ellipsometer is used to determine the thickness of films. The changes in chemical structure after surface modification of the films have been verified by using FTIR spectra analysis. The appearance of peak around 2800–2900 cm−1 after surface treatment of low-k films confirms the incorporation of non-polar and hydrophobic group (–CH3). The water contact angle of as-deposited films (85°) is observed to be increased up to 102° after surface treatment using 20% TMCS concentration in hexane. This significant change in the water contact angle confirms the modification of film’s surface from hydrophilic to hydrophobic. The properties such as hardness (3.22 GPa) and elastic modulus (75 GPa) of surface modified low-k films using 20% TMCS have been determined by Nano-indentation technique. Dielectric constant of the film is observed to be lowered from 3.56 to 2.58 after surface treatment.

Bulletin of Materials Science, 2012

Journal of Materials Science Materials in Electronics, Oct 5, 2013

ABSTRACT In this work, we have investigated the effect of annealing temperature on physical, chem... more ABSTRACT In this work, we have investigated the effect of annealing temperature on physical, chemical and electrical properties of Fluorine (F) incorporated porous SiO2 xerogel low-k films. The SiO2 xerogel thin films were prepared by sol–gel spin-on method using tetraethylorthosilicate as a source of Si. The hydrofluoric acid was used as a catalyst for the incorporation of F ion in the film matrix. The thickness and refractive index (RI) of the films were observed to be decreasing with increase in annealing temperature with minimum value 156 nm and 1.31 respectively for film annealed at 400 °C. Based on measured RI value, the 34 % porosity and 1.53 gm/cm3 density of the film annealed at 400 °C have been determined. The roughness of the films as a function of annealing temperature measured through AFM was found to be increased from 0.9 to 1.95 nm. The Electrical properties such as dielectric constant and leakage current density were evaluated with capacitance–voltage (C–V) and leakage current density–voltage (J–V) measurements of fabricated Al/SiO2 xerogel/P–Si metal–insulator-semiconductor (MIS) structure. Film annealed at 400 °C, was observed to be with the lowest dielectric constant value (k = 2) and with the lowest leakage current (3.4 × 10−8 A/cm2) with high dielectric breakdown

Microelectronics Reliability, Jan 1, 2011

A vital parameter interconnect capacitance in the ULSI has been investigated in this paper. The p... more A vital parameter interconnect capacitance in the ULSI has been investigated in this paper. The potential and static capacitance under the metal line strip has been determined by solving the Poisson’s equation by finite difference method. It has been observed that, the lowering of interconnect width and spacing between the two metal lines affect significantly on coupling capacitance. The total