Sandwich damascene resistor

A device comprising:

• a substrate;
• an interlayer dielectric (ILD) on the substrate;
• a first dielectric layer on the ILD;
• a first cavity formed in the first dielectric layer;
• a layer of resistive material lining the first cavity;
• and
• a second dielectric layer filling the first cavity.

A method comprising:

• forming at least one pair of source/drain regions in a substrate;
• forming an interlayer dielectric (ILD) on the substrate;
• forming a replacement metal gate (RMG) on the substrate in the ILD between each pair of source/drain regions;
• forming on the ILD and RMGs a first dielectric layer and a first sacrifice layer (SL);
• etching a portion of the first SL and first dielectric layer, forming a first cavity;
• conformally depositing a layer of first resistive material over the first SL and in the first cavity;
• depositing a second dielectric layer over the layer of first resistive material and filling the first cavity;
• planarizing the second dielectric layer, the layer of first resistive material, and the first SL down to an upper surface of the first dielectric layer;
• forming a second SL;
• etching a portion of the second SL and the first dielectric layer, forming a second cavity;
• conformally forming a layer of second resistive material over the second SL and in the second cavity;
• forming a third dielectric layer over the layer of second resistive material and filling the second cavity;
• planarizing the third dielectric layer, the layer of second resistive material, and the second SL down to the upper surface of the first dielectric layer;
• forming a fourth dielectric layer over the entire substrate;
• and
• forming contacts through the fourth dielectric layer and through the second and third dielectric layers to the layer of first resistive material and the layer of second resistive material, respectively, forming source/drain contacts through the fourth dielectric layer to the source/drain regions, and forming gate contacts through the fourth dielectric layer to the RMGs.