4-Colours/2-Junctions of III-V semiconductors on Si to use in electronics devices and solar cells

Project Information

4SUNS

Grant agreement ID: 758885

DOI

10.3030/758885

EC signature date 27 October 2017

Start date 1 February 2018

End date 30 September 2026

Funded under

• EXCELLENT SCIENCE - European Research Council (ERC)

Total cost

€ 1 499 719,00

EU contribution

€ 1 499 719,00

Coordinated by

UNIVERSIDAD AUTONOMA DE MADRID
Spain

Periodic Reporting for period 2 - 4SUNS (4-Colours/2-Junctions of III-V semiconductors on Si to use in electronics devices and solar cells)

Reporting period: 2023-04-01 to 2024-09-30

Summary of the context and overall objectives of the project

It is known that energy generation and storage are some of the problems of current society and the environment. Among the possible solutions proposed, solar energy is accepted as one of them. From semiconductor materials, electrical energy can be generated through the use of solar cells. Solar cells allow the absorption of photons from the sun, converting them into electrical energy. Among the abundant and non-contaminating semiconductor materials is silicon, with Si solar cells being the most marketed, offering an alternative for environmentally friendly electricity generation. There are other semiconductor materials that allow for better device efficiencies compared to Si, such as semiconductors formed by the III-V groups. Although these materials may have better performance, they are hindered by the need to be grown on substrates like Ge or GaAs, which are costly. In the 4SUNS project, we are developing III-V semiconductors on Si substrates to achieve high-efficiency solar cells at low cost. To grow III-V semiconductors on Si, we are using highly lattice-mismatched materials, which we have shown to have better utilization of the solar spectrum, able to absorb from 3 different spectral regions. Additionally, these materials have demonstrated new optoelectronic and electrical properties that are allowing us to develop a new device with the essence of a microchip, offering an opportunity for the fields of microelectronics and solar energy.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

III-V semiconductors on Silicon (Si) substrate reducing drastically the cost of the high efficiency solar cells. Also, the HMA materials have demonstrated to present three active energy bands which can absorbed in three different spectral regions increasing the photocurrent extraction of the solar cells keeping high open circuit voltage breaking the Schockley and Queisser limit of the conventional solar cells. 4SUNS project is developing this III-V-N to obtain a multiband solar cell on Si substrates.
To develop this new solar cell, we have purchased a molecular beam epitaxial system preciously designed. The project is divided in 3 different tasks. During the first 15 months, I estimated time needed to design, purchase, and calibrate the system, considering these tasks as medium risk due to the possible delays with the components of the MBE system during the purchase period and with the assemble process. Once the system would be calibrated during the next 3 years the structures will be develop. Currently, at 30 months, during the development substrate, we should get the quaternary alloy GaAs1-x-yNxPy on Si substrates having obtained the quaternary alloy on GaP substrate before, to start with the blocking layers growth. Using the chemical beam epitaxial system we have grown the quaternary on Si. Currently, the MBE system is under calibration process to reproduce our previous results.
We have also characterized the samples obtained new electrical properties. The results have demonstrated a breakthrough in the microelectronic field.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

Three energy active bands devices have demonstrated new optoelectronic and electrical properties.
Beyond the state of the art, the electrical measurements have shown that in a single structure device we have the essential of a micro-chip with an extraordinary control of current and voltage of the device. These new electrical properties are a breakthrough in the microelectronic field opening a new research field. In addition, to develop a new solar cell with 4 actives spectrum region we have grown GaAsNP alloy on Si substrate.