Stmicroelectronics S.r.l.

3Sun S.r.l.

Cosimo Gerardi

Sebastiano Ravesi

Marina Foti

Cristina Tringali

Salvatore Lombardo

Stella Loverso

Corrado Accardi

NoemiGraziana Sparta′

Noemi Graziana Sparta

Massimo Melanotte

Isodiana Crupi

Noemi Graziana Sparta′

Marcello Sciuto

NoemiGraziana Sparta'

Silvestra DiMarco

Nicola Costa

Silvestra Dimarco

Antonio Terrasi

Giuseppe Condorelli

Andrea Canino

Anna Battaglia

Giacomo Torrisi

Grazia Litrico

Alessandro Furnari

Alfredo Di Matteo

Salvatore Bellino

In multijunction photovoltaic cells, such as for example tandem solar cells having a top sub-cell and a crystalline silicon based bottom sub-cell, efficiency of conversion of solar energy into electrical energy is limited mainly by the junction between a top sub-cell and a bottom sub-cell of the multijunction photovoltaic cell. A multijunction photovoltaic cell of this disclosure at least partially overcomes this drawback because it has an intermediate layer of silicon nitride deposited in a conformal manner with a thickness of between 1 and 10 nm so as to define a P-N tunnel junction between the top sub-cell and the bottom sub-cell. A related fabrication process is also disclosed.

Multijunction photovoltaic cell and related method of fabrication

A solar cell including at least a first layer made of a semiconductor material for absorbing photons from light radiation and releasing charge carriers, and at least one conductive layer, overlapping the first layer, adapted to allow the light radiation to enter into the solar cell towards the first layer and to collect the charge carriers released by the first layer, the solar cell where the conductive layer includes at least three overlapped layers, including a transparent intermediate metal layer, made of metal, and two transparent oxide layers, made of a conductive oxide, where the two oxide layers are an inner oxide layer and an outer oxide layer surrounding the transparent intermediate metal layer to provide a low resistance path for the electrical charges and to maximize the amount of light radiation entering the solar cell. The embodiments also include a solar cells module including said solar cell.

Solar cell and solar cells module

A photovoltaic cell may include a hydrogenated amorphous silicon layer including a n-type doped region and a p-type doped region. The n-type doped region may be separated from the p-type doped region by an intrinsic region. The photovoltaic cell may include a front transparent electrode connected to the n-type doped region, and a rear electrode connected to the p-type doped region. The efficiency may be optimized for indoor lighting values by tuning the value of the H2/SiH4 ratio of the hydrogenated amorphous silicon layer.

Photovoltaic cell

Solar thin film modules are provided with reduced lateral dimensions of isolation trenches and contact trenches, which provide for a series connection of the individual solar cells. To this end lithography and etch techniques are applied to pattern the individual material layers, thereby reducing parasitic shunt leakages compared to conventional laser scribing techniques. In particular, there may be series connected solar cells formed on a flexible substrate material that are highly efficient in indoor applications.

Thin film solar cell module including series connected cells formed on a flexible substrate by using lithography

A photovoltaic cell may include a hydrogenated amorphous silicon layer including a n-type doped region and a p-type doped region. The n-type doped region may be separated from the p-type doped region by an intrinsic region. The photovoltaic cell may include a front transparent electrode connected to the n-type doped region, and a rear electrode connected to the p-type doped region. The efficiency may be optimized for indoor lighting values by tuning the value of the H/SiHratio of the hydrogenated amorphous silicon layer.

A thin film amorphous silicon solar cell may have front contact between a hydrogenated amorphous silicon layer and a transparent conductive oxide layer. The cell may include a layer of a refractory metal, chosen among the group composed of molybdenum, tungsten, tantalum and titanium, of thickness adapted to ensure a light transmittance of at least 80%, interposed therebetween, before growing by PECVD a hydrogenated amorphous silicon p-i-n light absorption layer over it. A refractory metal layer of just about 1 nm thickness may effectively shield the oxide from the reactive plasma, thereby preventing a diffused defect when forming the p.i.n. layer that would favor recombination of light-generated charge carriers.

Thin refractory metal layer used as contact barrier to improve the performance of thin-film solar cells

Thin film solar cell module including series-connected cells formed on a flexible substrate by using lithography

This invention relates to a memory cell which comprises a capacitor having a first electrode and a second electrode separated by a dielectric layer. Such dielectric layer comprises a layer of a semi-insulating material which is fully enveloped by an insulating material and in which an electric charge is permanently present or trapped therein. Such electric charge accumulated close to the first or to the second electrode, depending on the electric field between the electrodes, thereby defining different logic levels.

Memory cell structure integrated on semiconductor

Growing community of inventors

Motta S. Anastasia, Italy

Cosimo Gerardi