The MIS Inversion Layer Cell

The inversion layer cell has been studied by a number of workers so, 58 72 This type of cell utilises the fact that inherent to a thermally oxidised silicon surface is a sheet of positive charge located in the oxide near the oxide-silicon interface. This charge is fixed, stable, process dependent and highly predictable . 

The advantage of this type of cell over the conventional MIS technique is that it removes the necessity for the very thin semitransparent barrier metal layer. It is advantageous compared with the diffused junction cell in that it gives an ultra thin junction leading to an enhanced UV and blue response and requires no high temperature processing. 

Recently the performance of the TiO cell has been improved by the addition of a p f BSF region on the wafer. Using 4 0 2 cm p-type silicon wafers a 2% increase in efficiency has been observed compared with identical cells made without the BSF. This increased AMI efficiency results from an increase in V of 60 mV and an increase in I 4.5 mA/cm. This change in I is markedly 

The SiOa MIS cell was more difficult to produce since two 

550 mV and fill factors 0.75. Cells of both types have been made on semicrystalline cast silicon substrates with very encouraging results 

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