One-time programmable memory capacitor structure and manufacturing method thereof

A manufacturing method of a one-time programmable memory (OTP memory) capacitor structure, comprising steps of:

• providing a semiconductor substrate;
• forming a bottom electrode on the semiconductor substrate;
• forming a capacitor insulating layer on the semiconductor substrate to cover the bottom electrode;
• forming a metal layer on the capacitor insulating layer;
• forming a first insulating sacrificial layer on the metal layer;
• forming a capping layer on the first insulating sacrificial layer;
• forming a second insulating sacrificial layer on the capping layer;
• forming a patterned mask layer on the second insulating sacrificial layer, wherein the patterned mask layer has a plurality of patterned openings, and part of the second insulating sacrificial layer is exposed through the plurality of patterned openings;
• performing a first etching process to use the patterned mask layer as an etching mask to remove part of the second insulating sacrificial layer, part of the capping layer and part of the first insulating sacrificial layer;
• removing the patterned mask layer;
• and
• performing a second etching process to remove the second insulating sacrificial layer, and use the retained remaining part of the capping layer as an etching mask to remove part of the metal layer to expose part of the capacitor insulating layer, wherein the remaining part of the capping layer, the remaining part of the first insulating sacrificial layer, and the remaining part of the metal layer are sequentially stacked to form a metal electrode stack structure.