**Author details**

cells, which can be realized by improving passivation, electrodes, improving short wave-

General road to increase conversion efficiency is related to multijunction (MJ) design and fabrication of PV structures comprising materials with different bandgaps adjusted for harvesting maximum of solar energy spectrum. This has been demonstrated by MJ solar cells with

Therefore, MJ approach should be taken into account considering further development of HJT

semiconductors provided the highest reported values of PCE = 46% [15].

Hereby the authors declare a lack of any known for them conflicts of interests.

c-Si, (p)c-Si, (n) c-Si un-doped crystalline silicon, p- and n-doped crystalline silicon

PECVD plasma-enhanced chemical vapor deposition

FTIR Fourier transform spectroscopy

PCE, η, power conversion efficiency

TCO transparent conductive oxide

i-a-SiH un-doped amorphous silicon p-a-Si:H p-doped amorphous silicon n-a-Si:H n-doped amorphous silicon

i-μc-SiH un-doped microcrystalline silicon n-μc-SiH n-doped microcrystalline silicon p-μc-SiH p-doped microcrystalline silicon

p-SiC:H p-doped microcrystalline silicon carbide

Eg optical gap, eV

ITO indium tin oxide

ATR IR attenuated total reflection infrared spectroscopy

HJT heterojunction technology (devices, solar cells)

IBC interdigitated back contact (solar cells)

PV photovoltaic (structures, solar cells)

length collection by frontal interface, and so on.

c-Si solar cells with efficiency above 34%.

**Conflict of interest**

74 Solar Panels and Photovoltaic Materials

**Nomenclature**

A3 B5

> Eugenii Terukov1 , Andrey Kosarev2 \*, Alexey Abramov1 and Eugenia Malchukova3 ,

\*Address all correspondence to: akosarev@inaoep.mx

1 R and D Center TFTE, Polytechnicheskaya, St-Petersburg, Russia

2 National Institute for Astrophysics, Optics and Electronics, Puebla, Mexico

3 Ioffe Institute, Polytechnicheskaya, St-Petersburg, Russia
