Skip to Main content Skip to Navigation
Theses

Vers une ingénierie de bandes des cellules solaires à hétérojonctions a-Si:H / c-Si. Rôle prépondérant de l'hydrogène.

Abstract : This thesis is the first such work in France on a-Si:H/c-Si heterojunction solar cells. This technology is based on the deposition of amorphous silicon onto crystalline silicon substrates, thus enabling the fabrication of high efficiency solar cells entirely at low temperatures (< 200 °C). It also makes it possible to process very thin c-Si substrates (<150 μm). In this work, we have dealt exclusively with p-type doped c-Si substrates, upon which a-Si:H, pm-Si:H or μc-Si layers have been deposited by RF-PECVD. We have paid particular attention to the ITO deposition, the cleaning procedure steps, and the resulting reproducibility issues. Industrialization was one of the goals of the research; hence, solar cells with large areas (25 cm2) and using a low-cost, screen-printed metallization step were developed. Power conversion efficiencies of the resulting
cells were improved from 9 % to 17 % and record values of Voc between 660 mV and 677 mV were achieved. An outstanding quality of passivation (surface recombination of 16 cm/s averaged over 25 cm2) has been obtained.

We have carried out in-situ ellipsometric measurements, SIMS, HR-TEM, capacitance measurements, and numerical simulations in order to gain further insight in the poorly understood physics of heterojunction solar cells. Original results have been obtained, and as well, some existing paradoxes have been resolved concerning the role of “ion bombardment”, the impact of epitaxial growth, and the behaviour of band offsets. One of our major conclusions is that the band offsets of a-Si:H/c-Si heterojunctions are not constant and are especially governed by hydrogen
content. This discovery opens the door to the possibility of engineering heterojunction band offsets.
Document type :
Theses
Complete list of metadatas

Cited literature [160 references]  Display  Hide  Download

https://pastel.archives-ouvertes.fr/tel-00259575
Contributor : Jérôme Damon-Lacoste <>
Submitted on : Thursday, February 28, 2008 - 3:31:27 PM
Last modification on : Wednesday, March 27, 2019 - 4:20:03 PM
Long-term archiving on: : Thursday, May 20, 2010 - 11:45:08 PM

Identifiers

  • HAL Id : tel-00259575, version 1

Collections

Citation

J. Damon-Lacoste. Vers une ingénierie de bandes des cellules solaires à hétérojonctions a-Si:H / c-Si. Rôle prépondérant de l'hydrogène.. Matière Condensée [cond-mat]. Ecole Polytechnique X, 2007. Français. ⟨tel-00259575⟩

Share

Metrics

Record views

892

Files downloads

4085