Method of manufacturing semiconductor device
Provided is a technique for forming a film having a desired stress on a substrate. A method of manufacturing a semiconductor device includes: forming a film having a predetermined stress on a substrate by controlling a ratio of a thickness of a first film having compressive stress to a thickness of a second film having tensile stress by performing: (a) supplying an organic source gas containing a first element and a reactive gas containing a second element to the substrate to form the first film containing the first element and the second element; and (b) supplying an inorganic source gas containing the first element and the reactive gas to the substrate to form the second film containing the first element and the second element.
1. A method of manufacturing a semiconductor device, comprising:
(a) supplying an organic source gas containing a first element and a reactive gas containing a second element to a substrate having a photoresist pattern formed thereon while heating the substrate to a temperature ranging from 25° C. to 100° C. to form a first film on the photoresist pattern, wherein the first film has compressive stress and contains the first element and the second element; and (b) supplying an inorganic source gas containing the first element and the reactive gas to the substrate while heating the substrate to a temperature ranging from 25° C. to 100° C. to form a second film on the first film, wherein the second film has tensile stress and contains the first element and the second element, whereby a film comprising a laminated structure of the first film and the second film is formed on the photoresist pattern, the film having a predetermined stress by controlling a ratio of a thickness of the first film to a thickness of the second film, the predetermined stress being smaller than a stress of the photoresist pattern for forming a sidewall spacer in Self-Aligned Double Patterning.
2. The method of claim 1 ,
wherein the step (a) comprises:
(a-1) supplying the organic source gas to the substrate and removing the organic source gas, wherein the organic source gas further contains carbon;
(a-2) supplying the reactive gas to the substrate and removing the reactive gas; and
(a-3) repeating the step (a-1) and the step (a-2) to form the first film having a thickness (t x ) and a compressive stress (σ 1 ),
wherein the step (b) comprises:
(b-1) supplying the inorganic source gas to the substrate and removing the inorganic source gas, wherein the inorganic source gas is free of carbon;
(b-2) supplying the reactive gas to the substrate and removing the reactive gas; and
(b-3) repeating the step (b-1) and the step (b-2) to form the second film having a thickness (t y ) and a tensile stress (σ 2 ), and
wherein the predetermined stress of the film (σ 3 ) satisfies an equation
σ
1
t
x
-
σ
2
t
y
=
σ
3
.
3. The method of claim 2 , wherein the ratio is controlled such that the predetermined stress of the film (σ 3 ) is zero.
4. The method of claim 1 , wherein a top layer of the film comprises one of the first film and the second film selected according to a cleaning method of the substrate.
5. The method of claim 4 , wherein the top layer comprises the first film when the cleaning method is batch cleaning, and the top layer comprises the second film when the cleaning method is brush cleaning.
6. The method of claim 2 , wherein the predetermined stress of the film (σ 3 ) is a tensile stress smaller than the stress of the photoresist pattern in case where the stress of the photoresist pattern is a tensile stress.
7. The method of claim 2 , wherein the predetermined stress of the film (σ 3 ) is a compressive stress smaller than the stress of the photoresist pattern in case where the stress of the photoresist pattern is a compressive stress.