Film thickness monitoring structure for semiconductor substrate
A semiconductor substrate includes a wafer, a first stepped structure formed of plural stepped parts formed on a surface of the wafer with a first area occupation ratio, a second stepped structure formed of plural stepped parts formed on the surface of the wafer with a second, different area occupation ratio, and an interlayer insulation film formed on the surface so as to cover the first and second stepped structures, the interlayer insulation film having a planarized top surface, wherein there are provided at least first and second film-thickness monitoring patterns for monitoring film thickness on the surface in a manner covered by the interlayer insulation film, a first pattern group is formed on the surface such that the first pattern group comprises plural patterns disposed so as to surround the first film-thickness monitoring pattern, a second pattern group is formed on the surface such that the second pattern group comprises plural patterns disposed so as to surround the second film-thickness monitoring pattern, the first film-thickness monitoring pattern and the first pattern group having a third area occupation ratio on the surface, while the second film-thickness monitoring pattern and the second pattern group having a fourth area occupation ratio on the surface, wherein the third area occupation ratio is different from the fourth area occupation ratio.
1. A semiconductor substrate, comprising:
a wafer;
a plurality of stepped structures formed on a surface of said wafer with various area occupation ratios;
an interlayer insulation film formed on said surface of said wafer so as to cover said stepped structures, said interlayer insulation film having a planarized top surface,
said substrate carrying, on said surface, at least one film-thickness monitoring pattern for monitoring a film thickness of said interlayer insulation film in a state covered by said interlayer insulation film; and
a pattern group, formed on said wafer, formed of a plurality of patterns surrounding said film-thickness monitoring pattern,
wherein
each of said plurality of patterns has a square shape,
said plurality of patterns being formed with an area occupation ratio, including said film-thickness monitoring pattern, equal to said area occupation ratio of said stepped structures where said stepped structures are formed either most densely or most sparsely,
said wafer car in said film-thickness monitoring pattern and said plurality of patterns on a scribe line on said wafer.
2. The semiconductor substrate as claimed in claim 1 , wherein each of said film-thickness monitoring patterns has a square outer periphery, and each of said plurality of patterns has a square shape smaller than said film-thickness monitoring patterns.