Semiconductor device and manufacturing method of the same
AssigneesRenesas Technology Corp., Tokyo Electron Limited
InventorsToshihide Nabatame, Masaru Kadoshima, Hiroyuki Takaba
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Abstract
An object of the present invention is to simplify manufacturing process of an n channel MIS transistor and a p channel MIS transistor with gate electrodes formed of a metal material. For its achievement, gate electrodes of each of the n channel MIS transistor and the p channel MIS transistor are simultaneously formed by patterning ruthenium film deposited on a gate insulator. Next, by introducing oxygen into each of the gate electrodes, the gate electrodes are transformed into those having high work function. Thereafter, by selectively reducing the gate electrode of the n channel MIS transistor, it is transformed into a gate electrode having low work function.
Claims10
A manufacturing method of a semiconductor device, which comprises:
- an n channel MIS transistor with a first gate electrode formed in a first region on a main surface of a semiconductor substrate;
- and a p channel MIS transistor with a second gate electrode having work function higher than that of said first gate electrode formed in a second region on said main surface,
- said method comprising the steps of:
- (a) forming a gate insulator on said main surface of the semiconductor substrate;
- (b) after forming a metal film on said gate insulator, patterning said metal film to form a first gate electrode on said gate insulator in said first region and a second gate electrode on said gate insulator in said second region;
- (c) annealing said semiconductor substrate in an atmosphere containing oxygen to introduce said oxygen into said first and second gate electrodes;
- (d) after said step (c), covering said second gate electrode with a hydrogen barrier film;
- and
- (e) after said step (d), annealing said semiconductor substrate in an atmosphere containing hydrogen to make oxygen concentration in said first gate electrode lower than that in said second gate electrode.
A manufacturing method of a semiconductor device, which comprises:
- an n channel MIS transistor with a first gate electrode formed in a first region on a main surface of a semiconductor substrate;
- and a p channel MIS transistor with a second gate electrode having work function higher than that of said first gate electrode formed in a second region on said main surface,
- said method comprising the steps of:
- (a) forming a gate insulator on said main surface of the semiconductor substrate;
- (b) after forming a metal film on said gate insulator, patterning said metal film to form a first gate electrode on said gate insulator in said first region and a second gate electrode on said gate insulator in said second region;
- (c) annealing said semiconductor substrate in an atmosphere containing hydrogen to decrease oxygen concentration in said first and second gate electrodes;
- and
- (d) after said step (c), selectively ion-implanting oxygen into said second gate electrode to make the oxygen concentration in said second gate electrode higher than that in said first gate electrode.
Dependencies are inferred from the claim text.