โ Scribed by Armin G. Aber;e; Stefan Glunz; Wilhelm Warta
No coin nor oath required. For personal study only.
In this paper effective surface recombination velocities Ser f at the rear Si-SiO 2 interface of the presently best one-sun silicon solar cell structure are calculated on the basis of measured oxide parameters. A new cell design is proposed allowing for a control of the surface space charge region by a gate voltage. It is shown that the electric field introduced by the positive fixed oxide charge density typically found at thermally oxidized silicon surfaces and the favorable work function difference between the gate metal aluminum and silicon leads to a reduction of Seff to values well below 1 cm/s at AM1.5 illumination for n-type as well as p-type silicon. At low illumination levels, however, oxidized n-type silicon has much better surface passivation properties than p-type silicon due to the small hole capture cross section (or n/~rp = 1000 at midgap). Only at small illumination intensities for p-type substrates or in the case of poor Si-SiO 2 interface quality the incorporation of a gate electrode on the rear surface is a promising tool for further reducing surface recombination losses.
๐ SIMILAR VOLUMES
The present work reports the study and fabrication of violet polished and textunzed (viole~ black) silicon solar cells The cells were made with n-type silicon single crystal using boron diffusion m a reducing atmosphere. These cells are 16 cm 2 In area and have Va-A1 contacts in comb form and a sili
In this paper the present state of development of high efficiency silicon solar cells for use at high concentration levels (20X -100X) is described. The design factors and process steps leading to the best performance within the available process technology are analyzed. The cell efficiency has exce