Semiconductor device including via plug and method of forming the same

A semiconductor device, comprising:

• a lower insulating layer on a substrate;
• a plurality of conductive patterns in the lower insulating layer;
• a middle insulating layer on the lower insulating layer and the conductive patterns;
• a plurality of via control regions in the middle insulating layer, the via control regions being arranged between the plurality of conductive patterns, and the via control regions having a lower porosity than the middle insulating layer;
• an upper insulating layer on the middle insulating layer and the via control regions;
• and
• a via plug between the via control regions and connected to one selected from among the conductive patterns.

A semiconductor device, comprising:

• a lower insulating layer on a substrate;
• a conductive pattern in the lower insulating layer;
• a middle insulating layer on the lower insulating layer and the conductive pattern;
• a via control region formed in the middle insulating layer, the via control region including a material having a lower etch rate than the middle insulating layer;
• an upper insulating layer on the middle insulating layer and the via control region;
• a via plug passing through the via control region and connected to the conductive pattern;
• and
• an upper interconnection in the upper insulating layer and connected to the via plug.