Multiply Spin-Coated Ultra-Thick Hybrid Hard Mask for Sub 60nm MRAM Devices
First Claim
1. A method comprising:
- forming a stack of magnetic tunnel junction (MTJ) layers over a substrate;
forming a metal hard mask layer on the stack of MTJ layers;
forming a dielectric layer on the metal hard mask layer;
forming a hybrid mask layer on the dielectric layer, wherein the hybrid mask layers includes;
a first carbon-containing layer;
a first silicon-containing layer disposed on the first carbon-containing layer, the first silicon-containing layer having a first thickness;
a second carbon-containing layer disposed on the first silicon-containing layer; and
a second silicon-containing layer disposed on the second carbon-containing layer, the second silicon-containing layer having a second thickness that is different than first thickness;
patterning the second silicon-containing layer via a first process;
patterning the second carbon-containing layer, the first silicon-containing layer and the first carbon-containing layer via a second process; and
patterning the dielectric layer, the metal hard mask layer and the stack of MTJ layers via a third process.
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Accused Products
Abstract
A metal hard mask layer is deposited on a MTJ stack on a substrate. A hybrid hard mask is formed on the metal hard mask layer, comprising a plurality of spin-on carbon layers alternating with a plurality of spin-on silicon layers wherein a topmost layer of the hybrid hard mask is a silicon layer. A photo resist pattern is formed on the hybrid hard mask. First, the topmost silicon layer of the hybrid hard mask is etched where is it not covered by the photo resist pattern using a first etching chemistry. Second, the hybrid hard mask is etched where it is not covered by the photo resist pattern wherein the photoresist pattern is etched away using a second etch chemistry. Thereafter, the metal hard mask and MTJ stack are etched where they are not covered by the hybrid hard mask to form a MTJ device and overlying top electrode.
0 Citations
20 Claims
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1. A method comprising:
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forming a stack of magnetic tunnel junction (MTJ) layers over a substrate; forming a metal hard mask layer on the stack of MTJ layers; forming a dielectric layer on the metal hard mask layer; forming a hybrid mask layer on the dielectric layer, wherein the hybrid mask layers includes; a first carbon-containing layer; a first silicon-containing layer disposed on the first carbon-containing layer, the first silicon-containing layer having a first thickness; a second carbon-containing layer disposed on the first silicon-containing layer; and a second silicon-containing layer disposed on the second carbon-containing layer, the second silicon-containing layer having a second thickness that is different than first thickness; patterning the second silicon-containing layer via a first process; patterning the second carbon-containing layer, the first silicon-containing layer and the first carbon-containing layer via a second process; and patterning the dielectric layer, the metal hard mask layer and the stack of MTJ layers via a third process. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
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10. A method comprising:
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forming a stack of magnetic tunnel junction (MTJ) layers; forming a metal hard mask layer on the stack of MTJ layers; forming a hybrid mask layer on the metal hard mask layer, wherein the hybrid mask layers includes one or more carbon-containing layers and one or more silicon-containing layers; etching, using a first etchant, one of the silicon-containing layers from the one or more silicon-containing layers; etching, using a second etchant, one of the carbon-containing layers from the one o more carbon-containing layers, the second etchant being different from the first etchant; and etching the metal hard mask layer and the stack of MTJ layers. - View Dependent Claims (11, 12, 13, 14, 15, 16)
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17. A method comprising:
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forming a stack of magnetic tunnel junction (MTJ) layers; forming a top electrode layer directly on the stack of MTJ layers; forming a dielectric layer directly on the metal hard mask layer; spin coating a first carbon-containing layer directly on the dielectric layer; spin coating a first silicon-containing layer directly on the first carbon-containing layer; spin coating a second carbon-containing layer directly on the first silicon-containing layer; spin coating a second silicon-containing layer directly on the second carbon-containing layer; etching, via a first etching process, the second silicon-containing layer; etching, via a second etching process, the second carbon-containing layer, the first silicon-containing layer and the first carbon-containing layer, the second etching process being different than the first etching process; and etching, via a third etching process, the dielectric layer, the top electrode layer and the stack of MTJ layers. - View Dependent Claims (18, 19, 20)
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Specification