Semiconductor memory device and method for manufacturing the device
AssigneeKabushiki Kaisha Toshiba
InventorsHideaki Aochi, Mitsuru Sato, Eiji Yoshida
Life of this patent
Estimating the term…
Abstract
A semiconductor memory device includes a semiconductor substrate and a support layer provided above the semiconductor substrate. Particles are formed on the support layer. A first electrode is provided on the support layer such that it covers the particles. The first electrode has a first interface located opposite to the particles and being wavy in accordance with the pattern of the particles. A capacitor insulation film is provided on the first interface. The capacitor insulation film has a second interface located opposite to the first interface and being wavy in accordance with the shape of the first interface. A second electrode is provided on the capacitor insulation film.
Claims21
A semiconductor memory device having a capacitor structure, comprising:
- a semiconductor substrate;
- a support layer provided above the semiconductor substrate;
- a plurality of particles formed on the support layer;
- a first electrode provided on the support layer and covering the particles, the first electrode having a first interface opposite to the particles, the first interface being wavy in accordance with a pattern of the particles;
- a capacitor insulation film provided on the first interface, the capacitor insulation film having a second interface located opposite to the first interface, the second interface being wavy in accordance with a shape of the first interface;
- and
- a second electrode provided on the capacitor insulation film.
A method of manufacturing a semiconductor memory device having a capacitor structure, comprising:
- forming a support layer above a semiconductor substrate;
- depositing a material insulation film on the support layer, the material insulation film being substantially formed of a material selected from the group consisting of silicon and silicon nitride;
- cooling the material insulation film to make it collect into particles;
- forming a conductive film on the support layer such that the conductive film covers the particles, thereby providing a first electrode having a first interface located opposite to the particles, the first interface being wavy in accordance with a pattern of the particles;
- forming a capacitor insulation film on the first interface, the capacitor insulation film having a second interface opposite to the first interface, the second interface being wavy in accordance with a shape of the first interface;
- and
- forming a second electrode on the capacitor insulation film.
A method of manufacturing a semiconductor memory device having a capacitor structure, comprising:
- forming a first support layer above a semiconductor substrate;
- forming a second support layer on the first support layer;
- removing part of the second support layer, thereby forming a trench, the trench reaching the first support layer;
- depositing a material insulation film on an inner surface of the trench, the material insulation film being substantially formed of a material selected from the group consisting of silicon and silicon nitride;
- cooling the material insulation film to make it collect into particles;
- forming a conductive film on the inner surface of the trench such that the conductive film covers the particles, then removing the second support layer and the particles, thereby providing a first cylindrical electrode having a bottom, a side wall and a first interface, the first interface being located opposite to the particles and wavy in accordance with a pattern of the particles;
- forming a capacitor insulation film on the first interface, the capacitor insulation film having a second interface located opposite to the first interface, the second interface being wavy in accordance with a shape of the first interface;
- and
- forming a second electrode on the second interface.
Dependencies are inferred from the claim text.