Triple layer anti-reflective hard mask
AssigneesSpansion LLC, Globalfoundries Inc.
InventorsKouros Ghandehari, Hirokazu Tokuno, David Matsumoto, Christopher H. Raeder, Christopher Foster, Weidong Qian, Minh Van Ngo
Life of this patent
Estimating the term…
Abstract
A method includes forming a layer of silicon oxynitride (SiON), silicon rich nitride (SiRN) or silicon nitride (Si3N4) over a layer of semiconducting material. The method further includes forming a first layer of anti-reflective material over the layer of SiON, SiRN or Si3N4 and forming a second layer of anti-reflective material over the first layer. The method also includes using the first layer, second layer and layer of SiON, SiRN or Si3N4 as a mask when etching a pattern in the layer of semiconducting material.
Claims10
A method, comprising:
- forming a first layer directly on a layer of material, the first layer being formed to a thickness ranging from about 50 Å to about 250 Å, where the first layer comprises a layer of silicon oxynitride (SiON);
- forming a second layer directly on the first layer, the second layer being formed to thickness ranging from about 200 Å to about 600 Å, where the second layer comprises a layer of silicon nitride (Si3N4) and has an extinction coefficient ranging from about 0.9 to about 1.3;
- forming a third layer directly on the second layer, the third layer being formed to a thickness ranging from about 200 Å to about 400 Å, where the third layer comprises Si3N4 and has an extinction coefficient ranging from about 0.2 to about 0.5;
- and
- etching a pattern in the layer of material using the first layer, the second layer, and the third layer as a mask.
A method of forming a trench in a material, the method comprising:
- forming a layer of silicon oxynitride (SiON) directly on the material, the layer of SiON being formed to a thickness ranging from about 50 Å to about 250 Å;
- forming a first anti-reflective layer directly on the layer of SiON, the first anti-reflective layer having a first extinction coefficient ranging from about 1.0 to about 1.3 and comprising silicon nitride (Si3N4), the first anti-reflective layer being formed to a thickness ranging from about 200 Å to about 600 Å;
- forming a second anti-reflective layer directly on the first anti-reflective layer, the second anti-reflective layer having a second extinction coefficient ranging from about 0.2 to about 0.5 and comprising Si3N4, the second anti-reflective layer being formed to a thickness ranging from about 200 Å to about 400 Å;
- forming a first trench through the first anti-reflective layer, the second anti-reflective layer, and the layer of SiON;
- forming a second trench in the material through the first trench;
- and
- removing the first anti-reflective layer, the second anti-reflective layer, and the layer of SiON.
Dependencies are inferred from the claim text.