Semiconductor device and method of manufacturing the same
View Patent ↗Disclosed is a method of manufacturing a semiconductor device formed by laminating a capacitor including a bottom metal electrode, a capacitive insulating film, and an upper metal electrode. When the capacitive insulating film is formed by performing a first step of forming a first dielectric layer on the bottom metal electrode by a vapor phase film forming method using a precursor gas that contains constituent elements of a dielectric; and a second step of forming a second dielectric layer on the first dielectric layer by a vapor phase film forming method using a precursor gas that contains constituent elements of a dielectric, a film forming temperature in the first step is set so as to be lower than a film forming temperature in the second step.
1. A method of manufacturing a semiconductor device having a capacitor, where the capacitor is made by the method comprising the steps of:
laminating a bottom metal electrode, a capacitive insulating film on the bottom metal electrode, and an upper metal electrode on the capacitive insulating film,
wherein the step of laminating the capacitive insulating film includes a first step of laminating a first dielectric layer on the bottom metal electrode by a vapor phase film forming method using a precursor gas that contains constituent elements of a dielectric, and a second step of laminating a second dielectric layer on the first dielectric layer by a vapor phase film forming method using a precursor gas that contains constituent elements of a dielectric, and wherein a maximum temperature at which the first dielectric layer is laminated in the first step is lower than a temperature at which the second dielectric layer is laminated in the second step.
2. The method of manufacturing a semiconductor device, according to claim 1 , wherein an atomic layer deposition method is used as the vapor phase film forming method in the first step and the second step.
3. The method of manufacturing a semiconductor device, according to claim 2 , wherein the atomic layer deposition method in the first step and the second step performs alternately:
a step of forming a metal film by depositing metal, which is produced by reaction of a precursor gas that contains metal, on a film; and
a step of oxidizing the metal film by an oxidation gas and changing the oxidized metal film into a dielectric layer.
4. The method of manufacturing a semiconductor device, according to claim 3 , wherein vapor is used as the oxidation gas in the first step.
5. The method of manufacturing a semiconductor device, according to claim 3 , wherein an ozone gas is used as the oxidation gas in the second step.
6. The method of manufacturing a semiconductor device, according to claim 1 , wherein oxygen permeability of the first dielectric layer is set so as to be lower than oxygen permeability of the second dielectric layer.
7. The method of manufacturing a semiconductor device, according to claim 1 , wherein nitrogen is supplied in a film forming atmosphere in the first step.
8. The method of manufacturing a semiconductor device, according to claim 7 , wherein at least one of a silicon nitride and an aluminum oxide is used as a main material of the first dielectric layer formed in the first step.