Semiconductor device and manufacturing method thereof
View Patent ↗A capacitor uses niobium pentoxide in the manufacture of a semiconductor device. The niobium pentoxide has a low crystallization temperature of 600° C. that provides control over the oxidation of the bottom electrode during heat-treatment. A dielectric constituent present as an amorphous oxide along the grain boundaries of polycrystalline niobium pentoxide is used for a capacitor insulator, thereby providing a method to decrease the leakage current along the grain boundary of niobium pentoxide and to realize a high dielectric constant and low-temperature crystallization.
1. A semiconductor device comprising:
a first conducting film formed over a semiconductor substrate;
a dielectric deposited on said first conducting film; and
a second conducting film formed on said dielectric,
wherein said dielectric comprises a polycrystalline metal oxide with a first crystallization temperature, having a plurality of crystal grains, and an amorphous metal oxide with a second crystallization temperature higher than the first crystallization temperature, present at boundaries formed between said crystal grains,
wherein a metal material of said polycrystalline metal oxide is different from a metal material of said amorphous metal oxide, and
wherein said polycrystalline metal oxide comprises niobium pentoxide.
2. A semiconductor device comprising:
a first conducting film formed over a semiconductor substrate;
a dielectric deposited on said first conducting film; and
a second conducting film formed on said dielectric,
wherein said dielectric comprises a polycrystalline metal oxide with a first dielectric constant and first crystallization temperature, having a plurality of crystal grains, and an amorphous metal oxide, having a lower dielectric constant than said first dielectric constant and a higher crystallization temperature than said first crystallization temperature, present at boundaries formed between said crystal grains,
wherein a metal material of said polycrystalline metal oxide is different from a metal material of said amorphous metal oxide, and
wherein said polycrystalline metal oxide comprises niobium pentoxide.
3. A semiconductor device having a capacitor comprising:
a first electrode of said capacitor comprising a first conducting film formed over a semiconductor substrate;
a dielectric deposited on said first electrode; and
a second electrode of said capacitor comprising a second conducting film formed on said dielectric,
wherein the dielectric comprises a polycrystalline metal oxide with a first crystallization temperature, having a plurality of crystal grains, and an amorphous metal oxide with a second crystallization temperature higher than the first crystallization temperature, present at boundaries formed between said crystal grains,
wherein a metal material of said polycrystalline metal oxide is different from a metal material of said amorphous metal oxide, and
wherein said polycrystalline metal oxide comprises niobium pentoxide.
4. A semiconductor device according to claim 3 , wherein said first electrode comprises a material selected from ruthenium, platinum, copper, titanium nitride, tantalum nitride and tungsten nitride.
5. A semiconductor device according to claim 3 , wherein said first electrode comprises polycrystalline silicon.
6. A semiconductor device according to claim 1 , wherein the amorphous metal oxide comprises tantalum pentoxide.
7. A semiconductor device according to claim 6 , wherein the proportion of the amorphous metal oxide in said dielectric is from 5% to 50%.
8. A semiconductor device according to claim 1 , wherein the amorphous metal oxide comprises at least one oxide selected from among tantalum, silicon, titanium, and tungsten.
9. A semiconductor device according to claim 1 , wherein the film thickness of said dielectric is from 5 nm to 20 nm.
10. A semiconductor device according to claim 2 , wherein the amorphous metal oxide comprises tantalum pentoxide.
11. A semiconductor device according to claim 10 , wherein the proportion of the amorphous metal oxide in said dielectric is from 5% to 50%.
12. A semiconductor device according to claim 2 , wherein the amorphous metal oxide comprises at least one oxide selected from among tantalum, silicon, titanium, and tungsten.
13. A semiconductor device according to claim 2 , wherein the film thickness of said dielectric is from 5 nm to 20 nm.
14. A semiconductor device according to claim 3 , wherein the amorphous metal oxide comprises tantalum pentoxide.
15. A semiconductor device according to claim 14 , wherein the proportion of the amorphous metal oxide in said dielectric is from 5% to 50%.
16. A semiconductor device according to claim 3 , wherein the amorphous metal oxide comprises at least one oxide selected from among tantalum, silicon, titanium, and tungsten.
17. A semiconductor device according to claim 3 , wherein the film thickness of said dielectric is from 5 nm to 20 nm.