Buried MIM capacitor structure with landing pads
A buried metal-insulator-metal (MIM) capacitor with landing pads is formed between first and second semiconductor substrates. The landing pads provide increased area for contacting which may decrease the contact resistors of the capacitor. The area of the buried MIM capacitor can be varied to provide a tailored capacitance. The buried MIM capacitor is thermally stable since the MIM capacitor includes refractory metal or metal alloy layers as the capacitor plates.
1. A semiconductor structure comprising:
a first oxide layer located on a semiconductor substrate;
a metal-insulator-metal (MIM) capacitor located on the first oxide layer, wherein the MIM capacitor comprises a first refractory metal-containing layer, a dielectric material layer, and a second refractory metal-containing layer;
a second oxide layer located on the MIM capacitor; and
a semiconductor material device layer located on the second oxide layer, wherein the first oxide layer includes a first landing pad embedded therein, and the second oxide layer includes a second landing pad embedded therein.
2. The semiconductor structure of claim 1 , wherein the first landing pad is composed of a same refractory metal or refractory metal alloy as the first refractory metal-containing layer and is in direct physical contact with the first refractory metal-containing layer.
3. The semiconductor structure of claim 2 , wherein the second landing pad is composed of a same refractory metal or refractory metal alloy as the second refractory metal-containing and is direct physical contact with the second refractory metal-containing layer.
4. The semiconductor structure of claim 2 , wherein the second landing pad is composed of a same refractory metal or refractory metal alloy as the second refractory metal-containing layer and is spaced apart from with the second refractory metal-containing layer.
5. The semiconductor structure of claim 2 , wherein the second landing pad is composed of a different refractory metal or refractory metal alloy as the second refractory metal-containing layer and is spaced apart from with the second refractory metal-containing layer.
6. The semiconductor structure of claim 1 , further comprising a first metal-containing liner separating the first refractory metal-containing layer and the first landing pad from the first oxide layer.
7. The semiconductor structure of claim 1 , further comprising a second metal-containing liner separating the second refractory metal-containing alloy layer and the second landing pad from the second oxide layer.
8. The semiconductor structure of claim 1 , further comprising a second metal-containing liner separating the second refractory metal-containing alley layer from the second landing pad and the second oxide layer.
9. The semiconductor structure of claim 1 , further comprising first and second trench isolation structures extending from a topmost surface of the semiconductor material device layer and contacting a surface of the semiconductor substrate, wherein the MIM capacitor is located between the first and second trench isolation structures.
10. The semiconductor structure of claim 1 , further comprising a first contact structure extending from the topmost surface of the semiconductor material device layer and contacting a surface of the first landing pad, and a second contact structure extending from the topmost surface of the semiconductor material device layer and contacting a surface of the first landing pad.
11. The semiconductor structure of claim 1 , wherein the first refractory metal-containing layer comprises a patterned refractory metal or a patterned refractory metal alloy layer having a topography.
12. The semiconductor structure of claim 1 , wherein the second landing pad is laterally spaced from the second oxide layer by a metal-containing spacer.
13. The semiconductor structure of claim 1 , wherein the first refractory metal-containing layer is composed of a refractory metal or a refractory metal alloy.
14. The semiconductor structure of claim 13 , wherein the second refractory metal-containing layer is composed of a refractory metal or a refractory metal alloy.