Process for forming miniature contact holes in semiconductor device without short-circuit

A process for forming a hole, comprising the steps of:

• a) preparing a structure having a bottom layer, a first insulating layer covering said bottom layer and at least two conductive layers formed in said first insulating layer spaced apart from each other over said bottom layer in by a distance measured in a direction;
• b) forming a preliminary hole in said first insulating layer reaching said bottom layer and having a first length greater than said distance in said direction;
• c) forming a second insulating layer conformably extending on an upper surface of said first insulating layer and an inner surface defining said preliminary hole and said bottom layer;
• and
• d) etching said second insulating layer until said upper surface is exposed again so as to form a target hole having a second length less than said distance.