Method for manufacturing capacitor
View Patent ↗The present invention realizes high integration by utilizing an aluminum oxide as a capacitor insulating layer having a high dielectric constant, improving characteristics of a semiconductor device by using a low temperature vapordeposition and a low temperature annealing, improving leakage current characteristics by utilizing titanium as an upper electrode of the capacitor and reduces manufacturing costs by simplifying the capacitor manufacturing process. Therefore, the present invention is very useful and effective.
1. A method for manufacturing a capacitor comprising the steps of:
forming a field region and an active region on a semiconductor substrate,
thereafter forming first contact holes for connecting with the active region by stacking a first interlayer insulating layer on an entire region;
stacking a first connecting layer on the resultant structure;
filling metal in such a way that the first contact holes are buried to improve contact characteristics with the active region;
forming first plugs in the first contact holes by front etching;
forming a metal layer in the resultant structure;
forming a first photoresist layer by patterning on a portion for forming the capacitor and thereafter forming a capacitor by etching the metal layer;
forming a capacitor insulating layer on a top surface and a side surface of the capacitor and thereafter forming a second connecting layer;
forming a first metal line, patterning by stacking a second photoresist layer so as to block a capacitor region;
exposing the first interlayer insulating layer by sequentially etching the first metal line and the second connecting layer through the patterned second photoresist;
forming a second interlayer insulating layer on the resultant structure and thereafter forming second contact holes connected to the first metal line by a photolithography process; and
forming second plugs in the second contact holes and thereafter forming a second metal line for use in an interconnection.
2. The method of claim 1 , wherein the first connecting layer is a stacked layer including titanium (Ti)/titanium nitride (TiN) formed at a range of 50˜150 Å/100˜200Å, respectively.
3. The method of claim 1 , comprising forming tungsten by a chemical vapor deposition method, and thereafter forming the first plugs by patterning using a dry etching process.
4. The method of claim 1 , comprising forming the metal layer of aluminum at a temperature ranging from 300° C. to 500° C. at a thickness ranging from 3000 Å to 4000 Å.
5. The method of claim 1 , comprising etching the metal layer using dry etching.
6. The method of claim 1 , comprising forming the capacitor insulating layer by annealing an aluminum oxide (Al 2 O 3 ) layer at a temperature ranging from 200° C. to 400° C. at a thickness ranging from 30 Å to 100 Å.
7. The method of claim 1 , comprising forming the second connecting layer of titanium (Ti) with a thickness of 50 Å to about 150 Å.
8. The method of claim 1 , wherein the first metal line is a stack layer made of Al/Ti/TiN.
9. The method of claim 1 , comprising forming the first metal line by using a dry etching process.