Abstract
Abstract
The paper investigates the influence of the insulation
resistance of the responsive elements and the guard ring of a
silicon 4-quadrant photodiode on its dark currents. It was found
that a decrease in the insulation resistance leads to an increase in
the dark current of the guard ring and responsive elements. It was
found that the insulation resistance deteriorates due to the
formation of surface inversion layers at the interface
Si-SiO2. A method of increasing the insulation resistance of
the active elements of the photodiode by etching oxide in the gaps
between the responsive elements is proposed, thereby removing the
conductive inversion channels. In the absence of an increase in the
insulation resistance after these modifications, it is proposed to
etch the surface layer of silicon in the gaps between the responsive
elements by chemical-dynamic polishing with a gold masking
layer. The proposed methods make it possible to significantly reduce
the dark currents of the photodiodes, increase the insulation
resistance between the responsive elements, and increase the
percentage of yield of suitable products.