| 摘要 |
PURPOSE:To bore a contact hole having excellent uniformity without lowering the degree of integration by boring the contact hole to insulating films of three layers by utilizing differences among properties to an etching of the films. CONSTITUTION:An element isolation region 204, a silicon gate 203 and source- drain regions 202 are formed to a semiconductor substrae 201, and a first insulating film 209, a second insulating film 210 and a third insulating film 211 are grown through methods of vapor phase growth, etc. An insulating film, a property thereof to an etching differs from other insulating films, is selected as the second insulating film at that time. When etching the third insulating film, an insulating film having a large etching selection ratio with the second insulating film is applied. The second thin insulating film is etched through dry etching, etc., the first insulating film is removed through isotropic etching such as RIE, and contact holes are bored. |
