Electrically adjustable resistor

An electrically adjustable resistor pair comprising:

• a substrate;
• an adjustment region comprising a portion of the substrate doped with ions;
• a primary dielectric layer disposed on top of the substrate and in contact with the adjustment region, the primary dielectric layer including a first hole adapted to receive a first metal contact and a second hole adapted to receive a second metal contact, wherein the first and second metal contacts are each electrically connected to the adjustment region;
• a voltage source electrically connected between the first metal contact and the second metal contact such that a voltage is applied across the adjustment region;
• a first polysilicon resistive layer deposited on top of the primary dielectric layer and situated above the adjustment region and between the first and second metal contacts and closer to the first metal contact than to the second metal contact;
• and
• a second polysilicon resistive layer deposited on top of the primary dielectric layer and situated above the adjustment region and between the first and second metal contacts and closer to the second metal contact than to the first metal contact;
• wherein the first polysilicon resistive layer is adapted to act as a first variable resistor, and the second polysilicon resistive layer is adapted to act as a second variable resistor, wherein resistances of the first and second variable resistors can be adjusted by varying the voltage applied across the adjustment region by the voltage source.

A method for producing an electrically adjustable resistor comprises:

• creating an adjustment region by doping a substrate with ions;
• depositing a dielectric layer on top of the substrate and in contact with the adjustment region;
• forming a first hole and a second hole through the dielectric layer such that the first and second holes are located above the adjustment region;
• placing a first metal contact into the first hole and a second metal contact into the second hole such that the first and second metal contacts are each electrically connected to the adjustment region;
• depositing a polysilicon resistive layer onto the dielectric layer above the adjustment region and between the first and second metal contacts;
• adapting the polysilicon resistive layer to act as a variable resistor by connecting it to an electrical circuit;
• connecting a voltage source between the first metal contact and the second metal contact to create a voltage across the adjustment region;
• and
• varying the voltage across the adjustment region to cause a change in a resistance of the variable resistor.

A method for producing an electrically adjustable resistor comprises:

• creating a first adjustment region by doping a substrate with ions;
• depositing a first dielectric layer on top of the substrate and in contact with the first adjustment region;
• forming a first hole and a second hole through the first dielectric layer such that the first and second holes are located above the first adjustment region;
• placing a first metal contact into the first hole and a second metal contact into the second hole such that the first and second metal contacts are each electrically connected to the first adjustment region;
• depositing a polysilicon resistive layer onto the first dielectric layer above the first adjustment region and between the first and second metal contacts;
• depositing a second dielectric layer on top of the polysilicon resistive layer such that it extends beyond and around the polysilicon resistive layer;
• forming a third hole and a fourth hole in the second dielectric layer such that the third and fourth holes are located above the polysilicon resistive layer;
• placing a first metal resistor contact into the third hole and a second metal resistor contact into the fourth hole such that the first and second metal resistor contacts are each electrically connected to the polysilicon resistive layer;
• depositing a second adjustment layer on top of the second dielectric layer above the polysilicon resistive layer and between the first and second metal resistor contacts;
• adapting the polysilicon resistive layer to act as a variable resistor by connecting the first and second metal resistor contacts to an electrical circuit;
• connecting a first voltage source between the first metal contact and the second metal contact to create a first voltage across the first adjustment region;
• connecting a second voltage source between a first edge of the second adjustment layer and a second edge of the second adjustment layer to create a second voltage across the second adjustment region;
• varying the first voltage across the first adjustment region to cause a change in a resistance of the variable resistor;
• and
• varying the second voltage across the second adjustment region to cause a further change in the resistance of the variable resistor.