| 摘要 |
PURPOSE:To facilitate to increase the number of wiring layers, and to reduce also a wiring pitch when an interlayer insulating film is to be formed in an IC by a method wherein the film thereof is formed as to flatten completely unevenness of the groundwork, and upper and lower wirings connecting through holes are opened limiting to the parts having the equal thickness of the insulating film, and moreover at the thinnest parts. CONSTITUTION:An element isolating oxide film 22 is provided at the peripheral part of an N type semiconductor substrate 20, and P type well regions 21 of the plural number are formed by diffusion on the surface layer part of the substrate 20 surrounded with the oxide film thereof. Then gate oxide films 23 are provided on the regions 21, a thin interlayer insulating film 25 is adhered on the whole surface containing the gate oxide films thereof, windows are opened, and first Al wirings 15 to come in contact with the regions 21 are formed. After then, a thick interlayer insulating film 27 is adhered on the film 25 to remove completely unevenness generated according to the wirings 15, etc., and through holes are dug selecting the parts having the same thickness of the interlayer insulating film thereof, and moreover at the thinnest parts. Then second Al wirings 17 to be connected to the wirings 15 are adhered extending on the film 27, and the whole surface containing the wirings thereof is covered with a surface protective film 29. |
