In this paper we show the results from indoor and outdoor measurements on solar cells and modules, manufactured with different bifacial and monofacial cell architectures and encapsulated in different configurations. Reflection/transmission, IV and IQE spectra of single-cell laminates were measured and used to determine the energy spectra for all heat loss and absorption processes, including thermalisation, recombination, entropy generation, parasitic absorption and electrical power generation. From these spectra, the effective heat input was calculated for front, rear and combined irradiance. The power output, bifacial gain and module operating temperature were monitored of single-cell laminates exposed to indoor irradiance as well as of full-size modules installed on our rooftop. We have found that the effective heat input for bifacial glass-glass modules is increasingly larger with increasing rear irradiance compared to monofacial modules. Measured temperatures of rooftop-installed modules strongly indicate that the effective heat transfer coefficient of glass-glass modules is higher than that of white back sheet modules. The observed combined effect of heat input and heat transfer is that only at rear irradiance fractions beyond 15% the additional heat input can cause the bifacial modules to be hotter than their monofacial counterpart, but the energy yield is still much higher due to the large bifacial gain. In the case of moderate albedo, the bifacial energy gain is not accompanied by a higher temperature of the bifacial module compared to the monofacial module.@en

Silicon nitride (SiNx) is a material with many applications and can be deposited with various deposition techniques. Series of SiNx films were deposited with HWCVD, RF PECVD, MW PECVD and LF PECVD. The atomic densities are quantified using RBS and ERD. The influence of the atomic densities on the Si¿N and Si¿Si bond structure is studied. The density of N¿N bonds is found to be negligible. New Si¿N FTIR proportionality factors are determined which increase with increasing N/Si ratio from 1.2 · 1019 cm¿ 1 for Si rich films (N/Si = 0.2) to 2.4 · 1019 cm¿ 1 for N rich films (N/Si = 1.5). The peak position of the Si¿H stretching mode in the FTIR spectrum is discussed using the chemical induction model. It is shown that especially for Si-rich films the hydrogen content affects the Si¿H peak position. The influence of the composition on the refractive index of the films is discussed on the basis of the Lorentz¿Lorenz equation and the Kramers¿Kronig relation. The decreasing refractive index with increasing N/Si ratio is primarily caused by an increase of the band gap. Keywords: Hot Wire CVD; Silicon nitride@en