Backplanes for display applications, and components for use therein

A process for forming a plurality of diodes on a substrate, the process comprising:

• depositing a conductive layer on the substrate;
• depositing a first doped semiconductor layer on the substrate over the conductive layer;
• patterning the conductive layer and the doped semiconductor layer to form a plurality of discrete conductive layer/first doped semiconductor layer areas;
• depositing an undoped semiconductor layer on the substrate over the plurality of discrete conductive layer/first doped semiconductor layer areas;
• and
• forming a plurality of second doped semiconductor layer areas on the opposed side of the undoped semiconductor layer from the plurality of discrete conductive layer/first doped semiconductor layer areas,
• whereby the plurality of discrete conductive layer/first doped semiconductor layer areas, the undoped semiconductor layer and the plurality of second doped semiconductor layer areas form a plurality of diodes on the substrate.

A process for forming a diode on a substrate, the process comprising:

• depositing a doped semiconductor layer on the substrate;
• forming two spaced areas of undoped semiconductor material on the opposed side of the doped semiconductor layer from the substrate;
• and
• forming two spaced areas of conductive material, each of said areas being in contact with one of the areas of undoped semiconductor material on the opposed side thereof from the doped semiconductor layer.

A driver for driving an electro-optic display having a source line and a balance line, the driver comprising:

• a first input arranged to receive a digital signal representative of the magnitude of the voltage to be applied to the source line;
• a second input arranged to receive a sign bit representative of the polarity of the voltage to be applied to the source line;
• at least one digital/analogue converter;
• a first output arranged to output a source line voltage the magnitude and polarity of which are determined by the signals received at the first and second inputs respectively;
• and
• a second output arranged to output a balance line voltage of opposite polarity to the source line voltage, the magnitude of the balance line voltage bearing a predetermined relationship to the magnitude of the source line voltage.

A driver for driving an electro-optic display having a source line and a balance line, the driver comprising:

• a first input arranged to receive a digital signal representative of the magnitude of the voltage to be applied to the source line;
• a second input arranged to receive a sign bit representative of the polarity of the voltage to be applied to the source line;
• a third input arranged to receive a digital signal representative of the magnitude of the voltage to be applied to the balance line;
• a first positive output digital/analogue converter;
• a second negative output digital/analogue converter;
• a first output arranged to output a source line voltage the magnitude and polarity of which are determined by the signals received at the first and second inputs respectively;
• a second output arranged to output a balance line voltage of opposite polarity to the source line voltage, the magnitude of the balance line voltage being determined by the signal received at the third input;
• a first reversing switch connected to the first and third inputs and the inputs of the first and second digital/analogue converters, the first reversing switch having a first position in which the first input is connected to the first digital/analogue converter and the third input is connected to the second digital/analogue converter, and a second position in which the first input is connected to the second digital/analogue converter and the third input is connected to the first digital/analogue converter;
• and
• a second reversing switch connected to the outputs of the first and second digital/analogue converters and the first and second outputs, the second reversing switch having a first position in which the first digital/analogue converter is connected to the first output and the second digital/analogue converter is connected to the second output, and a second position in which the first digital/analogue converter is connected to the second output and the second digital/analogue converter is connected to the first output.