Method for manufacturing silicide and semiconductor with the silicide
View Patent ↗The present invention is directed to a method of manufacturing silicide used to reduce a contact resistance at a contact of a semiconductor device and a semiconductor device with the silicide manufactured by the same method. The method comprises the steps of: (a) cleaning a semiconductor substrate with a transistor formed thereon, the transistor including a source electrode, a drain electrode and a gate electrode; (b) placing the cleaned semiconductor substrate into a sputter chamber in a deposition equipment, and forming silicide at the same time of depositing a metal film under a state where the semiconductor substrate is heated at a temperature of 450-600° C.; (c) removing residual metal film not used for the formation of silicide; and (d) annealing the semiconductor substrate. According to the present invention, since silicide is formed at the same time of depositing a cobalt film, there is an advantage of omission of a protection film formation process over the prior arts where silicide is formed by a post-heat treatment.
1. A method of manufacturing silicide, comprising the steps of:
(a) cleaning a semiconductor substrate with a transistor formed thereon, the transistor including a source electrode, a drain electrode and a gate electrode;
(b) placing the cleaned semiconductor substrate into a sputter chamber in a deposition equipment, and heating the semiconductor substrate to a temperature of from greater than 450 to 600° C.;
(c) initially forming a monosilicide at the same time as sputtering a metal film at a DC power of 2-10 KW under a state where the semiconductor substrate is heated at the temperature of from greater than 450 to 600° C.;
(d) removing residual metal film not used for the formation of silicide; and
(e) annealing the semiconductor substrate.
2. The method of claim 1 , wherein, in the step (c), the monosilicide comprises CoSi.
3. The method of claim 2 , wherein the step (a) includes a first cleaning step comprising cleaning the semiconductor substrate with SC1 solution.
4. The method of claim 3 , wherein the step (a) further includes a second cleaning step comprising cleaning the semiconductor substrate with HF or DHF (dilute HF) solution.
5. The method of claim 1 , wherein the step (a) includes plasma cleaning the semiconductor substrate in the sputter chamber.
6. The method of claim 5 , wherein the cleaning step includes a first etching step at an RF power 60-90 W and a second etching stop at an RF power of 250-350 W.
7. The method of claim 5 , wherein said plasma comprises argon gas of 3-8 sccm.
8. The method of claim 1 , wherein the step (c) comprises sputtering cobalt.
9. The method of claim 1 , wherein the step (c) comprises sputtering the metal film using argon gas of 40-70 sccm, and heating the semiconductor substrate using argon gas of 8-15 sccm.
10. The method of claim 2 , wherein the step (d) includes a first removal step comprising removing the metal film for 5-15 minutes in SPM solution at a temperature of 50-150° C. and a second removal step comprising removing the metal film for 3-10 minutes in SC1 solution at a temperature of 40-70° C.
11. The method of claim 2 , wherein the step (c) includes heating the semiconductor substrate for 10-60 seconds at a temperature of 700-950° C. in a RTP equipment.
12. The method of claim 2 , wherein the step (c) includes heating the semiconductor substrate for 20-60 minutes at a temperature of 500-900° C. in an electric furnace.
13. The method of claim 2 , wherein, after the step (e) the silicide comprises CoSi 2 .
14. A method of manufacturing silicide, comprising the steps of:
(a) cleaning a semiconductor substrate with a transistor thereon, the transistor including a source electrode, a drain electrode and a gate electrode;
(b) placing the cleaned semiconductor substrate into a sputter chamber and spattering a metal film at a DC power of 2-10 kW, while heating the semiconductor substrate at a temperature of 450 to 600° C. to form a silicide having 1:1 metal:silicon ratio;
(c) removing residual metal film; and
(d) annealing the semiconductor substrate.
15. The method of claim 14 , wherein the silicide comprises CoSi.
16. The method of claim 14 , wherein step (b) comprises sputtering the metal film using argon gas of 40-70 sccm, and heating the semiconductor substrate using argon gas of 8-15 sccm.
17. The method of claim 14 , wherein the step (c) includes a first removal step comprising removing the metal film for 5-15 minutes in SPM solution at a temperature of 50-150° C. and a second removal step comprising removing the metal film for 3-10 minutes in SC1 solution at a temperature of 40-70° C.
18. The method of claim 15 , wherein the step (d) includes rapid thermal processing the semiconductor substrate for 10-60 seconds at a temperature of 700-950° C.
19. The method of claim 15 , wherein the step (d) includes heating the semiconductor substrate for 20-60 minutes at a temperature of 500-900° C. in an electric furnace.
20. The method of claim 15 , wherein after the step (d) the silicide comprises CoSi 2 .