Silicon carbide nanolayers as a solar cell constituent

Thin films of predominantly amorphous n-type SiC were prepared by non-reactive magnetron sputtering in an Ar atmosphere. A previously synthesized SiC was used as a solidstate target. Deposition was carried out on a cold substrate of ptype Si (100) with a resistivity of 2Ωcm. The Raman spectrum shows a dominant band at 982 cm-¹, i.e., in the spectral region characteristic for SiC. It was found that the root mean squareroughness varies from about 0.3 nm to 9.0 nm when the film thickness changes from about 2 nm to 56 nm, respectively. Transmission electron microscopy studies showed that SiC thin films consist predominantly of an amorphous phase with inclusions of very fine nanocrystallites. A heterostructure consisting of a p-type Si (100) and a layer of predominantly amorphous n-type SiC was fabricated and studie

p Si n SiC NANOLAYER PHOTOVOLTAIC CELL

Thin films of amorphous SiC were prepared by non reactive magnetron sputtering in an Ar atmosphere. A previously synthesized SiC was used as a solid state target. Deposition was carried out on a cold substrate of p Si 100 with a resistivity of 2 Ohm amp; 61655;cm. The Raman spectrum shows a dominant band at 982 cm 1, i.e. in the spectral region characteristic for SiC. The film thickness determined from atomic force microscopy measurements was about 8 40 nm, the height of the structural units of the film was 1 2 nm, while the linear dimensions were of the order of tens of nanometers. The amorphous nature of SiC grown on the Si substrate is confirmed by the presence of the diffraction rings which indicate the absence of the dominant orientation of the prepared films. A heterostructure consisting of a p type Si 100 and a layer of amorphous n type SiC was fabricated and studied. The investigation of its electrical and photoelectric properties shows that the entire space charge region is located in Si. This is in addition confirmed by the spectral dependence of the p Si n SiC photo sensitivity. The barrier height at the p Si n SiC interface estimated from dark I V characteristics is of the order of 0.9 1.0 eV. Load I V characteristics of p Si n SiC amorphous nanolayer solar cells demonstrate under standard AM1.5 illumination conditions a conversion efficiency of 7.2

Silicon solar cells based on pSi/nSi3N4 nanolayers

Thin films of Si3N4 were prepared by non-reactive magnetron sputtering in an Ar atmosphere. A previously synthesized Si3N4 was used as a solid-state target. Deposition was carried out on a cold substrate of p-Si (100) with a resistivity of 2 Ohm cm. The Raman spectrum of the deposited Si3N4 layers has been investigate

A comparison of polarized and non-polarized human endometrial monolayer culture systems on murine embryo development

BACKGROUND: Co-culture of embryos with various somatic cells has been suggested as a promising approach to improve embryo development. Despite numerous reports regarding the beneficial effects of epithelial cells from the female genital tract on embryo development in a co-culture system, little is known about the effect of these cells when being cultured under a polarized condition on embryo growth. Our study evaluated the effects of in vitro polarized cells on pre-embryo development. METHODS: Human endometrial tissue was obtained from uterine specimens excised at total hysterectomy performed for benign indications. Epithelial cells were promptly isolated and cultured either on extra-cellular matrix gel (ECM-Gel) coated millipore filter inserts (polarized) or plastic surfaces (non-polarized). The epithelial nature of the cells cultured on plastic was confirmed through immunohistochemistry, and polarization of cells cultured on ECM-Gel was evaluated by transmission electron microscopy (TEM). One or two-cell stage embryos of a superovulated NMRI mouse were then flushed and placed in culture with either polarized or non-polarized cells and medium alone. Development rates were determined for all embryos daily and statistically compared. At the end of the cultivation period, trophectoderm (TE) and inner cell mass (ICM) of expanded blastocysts from each group were examined microscopically. RESULTS: Endometrial epithelial cells cultured on ECM-Gel had a highly polarized columnar shape as opposed to the flattened shape of the cells cultured on a plastic surface. The two-cell embryos cultured on a polarized monolayer had a higher developmental rate than those from the non-polarized cells. There was no statistically significant difference; still, the blastocysts from the polarized monolayer, in comparison with the non-polarized group, had a significantly higher mean cell number. The development of one-cell embryos in the polarized and non-polarized groups showed no statistically significant difference. CONCLUSION: Polarized cells could improve in vitro embryo development from the two-cell stage more in terms of quality (increasing blastocyst cellularity) than in terms of developmental rate

Silicon carbide nanolayers as a solar cell constituent

Thin films of predominantly amorphous n-type SiC were prepared by non-reactive magnetron sputtering in an Ar atmosphere. A previously synthesized SiC was used as a solidstate target. Deposition was carried out on a cold substrate of ptype Si (100) with a resistivity of 2Ωcm. The Raman spectrum shows a dominant band at 982 cm-¹, i.e., in the spectral region characteristic for SiC. It was found that the root mean squareroughness varies from about 0.3 nm to 9.0 nm when the film thickness changes from about 2 nm to 56 nm, respectively. Transmission electron microscopy studies showed that SiC thin films consist predominantly of an amorphous phase with inclusions of very fine nanocrystallites. A heterostructure consisting of a p-type Si (100) and a layer of predominantly amorphous n-type SiC was fabricated and studie

THE BIFACIAL CONVERTER OF SOLAR ENERGY IN ELECTRICAL ON THE BASE OF ISOTYPE HETEROJUNCTION

The method of n+Si/nSi/SiO2 /n+ITO bifacial solar cells fabrication by pyrolitical spraying was elaborated. This structure contains only isotype junctions. The spectral sensitivity is situated in the 350–1200nm wavelength region and is independent on the illumination direction. The photoelectrical parameters of solar cells obtained on silicon wafer (4,5 Ohm.cm) are following: at frontal illumination Voc=0,425V, Isc=32,63mA/cm2 , FF=68,3%, Eff=9,47%; at rear illumination Voc=0,392V, Isc =13,20mA/cm2 , FF=69,3%, Eff=3,60%

Silicon solar cells based on pSi/nSi3N4 nanolayers

Thin films of Si3N4 were prepared by non-reactive magnetron sputtering in an Ar atmosphere. A previously synthesized Si3N4 was used as a solid-state target. Deposition was carried out on a cold substrate of p-Si (100) with a resistivity of 2 Ohm cm. The Raman spectrum of the deposited Si3N4 layers has been investigate

the bifacial converter of solar energy in electrical on the base of isotype heterojunction

The method of n+Si/nSi/SiO2 /n+ITO bifacial solar cells fabrication by pyrolitical spraying was elaborated. This structure contains only isotype junctions. The spectral sensitivity is situated in the 350–1200nm wavelength region and is independent on the illumination direction. The photoelectrical parameters of solar cells obtained on silicon wafer (4,5 Ohm.cm) are following: at frontal illumination Voc=0,425V, Isc=32,63mA/cm2 , FF=68,3%, Eff=9,47%; at rear illumination Voc=0,392V, Isc =13,20mA/cm2 , FF=69,3%, Eff=3,60%