N‐type microcrystalline silicon carbide (μc‐SiC:H(n)) is a wide bandgap material that is very promising for the use on the front side of crystalline silicon (c‐Si) solar cells. It offers a high optical transparency and a suitable refractive index that reduces parasitic absorption and reflection losses, respectively. In this work, we investigate the potential of hot wire chemical vapor deposition (HWCVD)–grown μc‐SiC:H(n) for c‐Si solar cells with interdigitated back contacts (IBC). We demonstrate outstanding passivation quality of μc‐SiC:H(n) on tunnel oxide (SiO2)–passivated c‐Si with an implied open‐circuit voltage of 742 mV and a saturation current density of 3.6 fA/cm2. This excellent passivation quality is achieved directly after the HWCVD deposition of μc‐SiC:H(n) at 250°C heater temperature without any further treatments like recrystallization or hydrogenation. Additionally, we developed magnesium fluoride (MgF2)/silicon nitride (SiNx:H)/silicon carbide antireflection coatings that reduce optical losses on the front side to only 0.47 mA/cm2 with MgF2/SiNx:H/μc‐SiC:H(n) and 0.62 mA/cm2 with MgF2/μc‐SiC:H(n). Finally, calculations with Sentaurus TCAD simulation using MgF2/μc‐SiC:H(n)/SiO2/c‐Si as front side layer stack in an IBC solar cell reveal a short‐circuit current density of 42.2 mA/cm2, an open‐circuit voltage of 738 mV, a fill factor of 85.2% and a maximum power conversion efficiency of 26.6%.

This work demonstrates that the combination of a wet‐chemically grown SiO2 tunnel oxide with a highly‐doped microcrystalline silicon carbide layer grown by hot‐wire chemical vapor deposition yields an excellent surface passivation for phosphorous‐doped crystalline silicon (c‐Si) wafers. We find effective minority carrier lifetimes of well above 6 ms by introducing this stack. We investigated its c‐Si surface passivation mechanism in a systematic study combined with the comparison to a phosphorous‐doped polycrystalline‐Si (pc‐Si)/SiO2 stack. In both cases, field effect passivation by the n‐doping of either the µc‐SiC:H or the pc‐Si is effective. Hydrogen passivation during µc‐SiC:H growth plays an important role for the µc‐SiC:H/SiO2 combination, whereas phosphorous in‐diffusion into the SiO2 and the c‐Si is operative for the surface passivation via the Pc‐Si/SiO2 stack. The high transparency and conductivity of the µc‐SiC:H layer, a low thermal budget and number of processes needed to form the stack, and the excellent c‐Si surface passivation quality are advantageous features of µc‐SiC:H/SiO2 that can be beneficial for c‐Si solar cells. (© 2016 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)

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Background: Breastfeeding is the best preventive intervention and has potential impact on child morbidity and mortality. In spite of these demonstrated benefit of breastfeeding, the duration and prevalence are still low in first six months of life. The objectives of the study were to estimate the prevalence of the practices of breast feeding among those mother who have children < 2 years of age and to study the significance of association of risk factors with breast feeding among mothers of rural health training centre of JNUIMSRC, Jaipur. Methods: A cross sectional study was conducted in field practice areas of rural health training centre, JNUIMSRC, Jaipur. 204 mothers having children between 0-2 years age group were included by Purposive sampling method. Pretested Predesigned questionnaire was used to collect data. Results: Majority of the mothers were in age group of 18-22 years, Iliterate mothers were 20.6%, Primary level of education 57.4%. Awareness regarding exclusive breastfeeding was more among literates than illiterates (p<0.05). Pre lacteal feeds were practiced among 30.9% of mothers before initiation of breast feeding. Conclusions. Exclusive breastfeeding upto 0-6 months was practiced by 26.9% of mothers.

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