Semiconductor device manufacturing method and semiconductor device

Abstract

A manufacturing method of a semiconductor device having a highly reliable capacitor, and the semiconductor device are provided. The semiconductor device manufacturing method according to the present invention includes: a first step of forming a first electrode of a capacitor on a semiconductor substrate; a second step of forming a capacitor insulating film on the whole surface including a side surface and an upper surface of the first electrode; a third step of forming a protection insulating film made of a material different from that of the capacitor insulating film, on the capacitor insulating film; a fourth step of removing the protection insulating film and the capacitor insulating film from the upper surface of the first electrode, by anisotropically etching the protection insulating film and the capacitor insulating film; a fifth step of removing the protection insulating film that remains on the side surface of the first electrode; and a sixth step of forming a second electrode of the capacitor on the capacitor insulating film, after removing the protection insulating film.

Description

TECHNICAL FIELD [0001] The present invention relates to a semiconductor device manufacturing method and a semiconductor device. Particularly, the invention relates to a semiconductor device having a stacked capacitor, and a method of manufacturing the semiconductor device. BACKGROUND OF THE INVENTION [0002] Conventionally, in a DRAM (Dynamic Random Access Memory) having a stacked capacitor, in order to compensate for a decrease of electrostatic capacitance due to a reduction in the size of the capacitor, the height of the capacitor has been increased or a high dielectric material has been used for a capacitor insulating film. [0003] However, when the size of the capacitor further decreases in future, the above measure is not sufficient, and the configuration of the capacitor needs to be more complex. When the capacitor has a more complex configuration, a process of processing the capacitor insulating film becomes additionally necessary. For example, when a capacitor configuration in...

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Benefits of technology

[0009] The present invention has been achieved to solve the above problems. It is an object of the present invention to provide a manufacturing method of a semiconductor device having a highly reliable capacitor, which suppresses an etching damage on a capacitor insulating film of the capacitor and suppress occurrence of leakage current, and the semiconductor device.

[0010] It is another object of the invention to provide a semiconductor device that can suppress the occurrence of leakage current at the lower end of a capacitor insulating film of a capacitor, and a method of manufacturing this semiconductor device.

[0012] According to the semiconductor device manufacturing method of the present invention, the surface of the capacitor insulating film is protected by the protection insulating film, at the time of performing anisotropic etching of the capacitor insulating film. Therefore, an etching damage or a residual molecule of an etching product occurs on only the surface of the protection insulating film. Since the protection insulating film is removed after the etching, a damaged layer and a residual molecule of the protection insulating film can be completely removed. Therefore, the surface of the capacitor insulating film can be kept clean. Consequently, increase in the leakage current of the capacitor and reduction in reliability can be prevented.

[0013] Further, after performing the anisotropic etching, a part of the capacitor insulating film that extends in a direction of a second electrode is formed in a width corresponding to the film thickness of the protection insulating film, at a lower end of the capacitor insulating film. Accordingly, the occurrence of leakage current between a first electrode and a second electrode at the lower end of the capacitor insulating film can be suppressed.

[0015] According to the semiconductor device of the present invention, presence of the second part at the lower end of the capacitor insulating film can suppress the occurrence of leakage current between the first electrode and the second electrode at the lower end of the capacitor insulating film.

Problems solved by technology

Therefore, an etching damage or a residual molecule of an etching product occurs on only the surface of the protection insulating film.

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