Electrostatic discharge devices for integrated circuits

A diode array for use in discharging static electricity in integrated circuits, the diode array comprising:

• a silicon substrate;
• a first array of doped regions of the silicon substrate, the first array of doped regions having graduated widths and containing a first dopant species,
• a second array of doped regions of the silicon substrate, the second array of doped regions having graduated widths and containing a second dopant species, the second array interleaved with the first array so that pairs of adjacent doped regions overlap to form diode junctions, each diode junction characterized by an overlap width;
• and
• an array of interconnects providing access to couple electrical signals to the diode array.

A method of fabricating diodes for use in discharging static electricity in integrated circuits, the method comprising:

• depositing an implant mask on a surface of a silicon substrate that includes a buried oxide layer;
• patterning the implant mask with different sized mask openings;
• implanting dopant ions of a first type into the silicon substrate through the mask openings at a selected first angle and a selected first ion energy, each mask opening, in combination with the first angle and the first ion energy, determining a size of a first implanted region;
• implanting dopant ions of a second type into the silicon substrate through the mask openings at a selected second angle and a selected second ion energy, each mask opening, in combination with the second angle and the second ion energy, determining a size of a second implanted region;
• and
• annealing the silicon substrate to form diode junctions in overlap regions of the silicon substrate in which the first and second types of dopant ions coincide;
• removing the implant mask;
• and
• forming electrical contacts to the implanted regions.