Semiconductor device and method of producing the same
In a semiconductor device having element isolation made of a trench-type isolating oxide film 13 , large and small dummy patterns 11 of two types, being an active region of a dummy, are located in an isolating region 10 , the large dummy patterns 11 b are arranged at a position apart from actual patterns 9 , and the small dummy patterns 11 a are regularly arranged in a gap at around a periphery of the actual patterns 9 , whereby uniformity of an abrading rate is improved at a time of abrading an isolating oxide film 13 a is improved, and surface flatness of the semiconductor device becomes preferable.
1. A method of manufacturing a semiconductor device, comprising steps of:
(a) forming grooves in a semiconductor substrate;
(b) forming isolation regions by embedding first insulating films into the grooves, thereby an active device region, a plurality of first dummy patterns and a plurality of second dummy patterns are defined by the isolation regions; and
(c) forming a MISFET in the active device region,
wherein each of the first dummy patterns has the same planar size and is arranged with same pitch,
wherein each of the second dummy patterns has the same planar size and is arranged with same pitch,
wherein the planar size of each of the second dummy patterns is larger than the planar size of each of the first dummy patterns,
wherein, in a first direction and a second direction which is perpendicular to the first direction, the first dummy patterns abut to the active device region,
wherein, in the first direction and the second direction, the second dummy patterns abut to the active device region through the first dummy patterns, and
wherein, in the first direction, at least one of the second dummy patterns directly abuts to the active device region without the first dummy patterns.
2. A method of manufacturing a semiconductor device according to the claim 1 ,
wherein the step (b) is performed by using a CMP method.
3. A method of manufacturing a semiconductor device according to the claim 1 ,
wherein the MISFET is not formed in the first and second dummy patterns.
4. A method of manufacturing a semiconductor device according to the claim 3 ,
wherein the first and second dummy patterns are not electrically connected to the MISFET which is formed in the active device region.
5. A method of manufacturing a semiconductor device according to the claim 1 ,
wherein the first and second dummy patterns have the same conductive type, respectively.
6. A method of manufacturing a semiconductor device according to the claim 5 ,
wherein the first and second dummy patterns have p conductive type, respectively.
7. A method of manufacturing a semiconductor device according to the claim 1 ,
wherein the first insulating film is formed of a silicon oxide film.