MANUFACTURING METHOD OF SEMICONDUCTOR DEVICE

• Main Author: INUKAI KAZUAKI
• Format: Patent
• Language: English
• Published: 11.08.2005
• Edition: 7
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

PROBLEM TO BE SOLVED: To prevent voids (cavities) from being generated in the sidewalls of a trench and contact hole formed in a porous insulating film, in the manufacturing method of a semiconductor device having the porous insulating film. SOLUTION: When so etching an interlayer insulating film 5 including a porous low dielectric-constant film 3a as to form a contact hole 7a, fluorine A remains in the inside of the porous low dielectric-constant film 3a which is present near a sidewall 3b of the contact hole 7a, because of the use of a fluorine-based gas. When the fluorine remains therein, the fluorine is so dissolved in a water by the rinsing of a cleaning process performed thereafter, etc., and is so changed into a hydrofluoric acid as to generate voids in after-processes by etching the porous low dielectric-constant film 3a. Therefore, in order to remove the residual fluorine A, a semiconductor substrate 1 is irradiated from above it by a hydrogen radical B after forming the contact hole 7a. Then, the fluorine A is so substituted by a gaseous hydrofluoric acid C as to be able to remove the fluorine A without etching the porous low dielectric-constant film 3a. COPYRIGHT: (C)2005,JPO&NCIPI