Photoresist, method of manufacturing a semiconductor device and method of extreme ultraviolet lithography
A method of manufacturing a semiconductor device includes forming a multilayer photoresist stack over a substrate, in which the multilayer photoresist stack has a first photoresist layer and a second photoresist layer over the first photoresist layer, and the second photoresist layer is less reactive to hydrogen than the first photoresist layer, exposing the multilayer photoresist stack to an EUV radiation, and developing the exposed multilayer photoresist stack.
1 . A method of manufacturing a semiconductor device, comprising:
forming a multilayer photoresist stack over a substrate, wherein the multilayer photoresist stack has a first photoresist layer and a second photoresist layer over the first photoresist layer, and the second photoresist layer is less reactive to hydrogen radicals than the first photoresist layer, and wherein the second photoresist layer comprises:
a first component having a cross-linker;
a second component having a solubility control unit, wherein the second component further comprises:
a polymer backbone; and
an intermediate bonding unit, the solubility control unit is bonded to the polymer backbone through the intermediate bonding unit, and the intermediate bonding unit and the solubility control unit collectively form the following chemical structure:
a solvent, wherein the first component and the second component are dissolved in the solvent, the solvent is in aqueous phase; and
a photo acid generator (PAG) containing a cation consisting of:
and an anion consisting of:
exposing the multilayer photoresist stack to an EUV radiation; and
performing a developing step to develop both of the first photoresist layer and the second photoresist layer of the exposed multilayer photoresist stack such that the first photoresist layer forms separated first resist segments and the second photoresist layer forms separated second resist segments.
2 . The method of claim 1 , wherein the solvent is selected from the group consisting of tetramethylammonium hydroxide (TMAH), Tetrabutylammonium hydroxide (TBAH), KOH, NaOH, HCL, HF, and water.
3 . The method of claim 1 , wherein a sum of a content of the first component and a content of the second component are about 0.02 atomic percent (at %) to about 5 atomic percent (at %) based on a total content of the solvent.
4 . An extreme ultraviolet lithography (EUVL) method, comprising:
turning on a droplet generator to eject a metal droplet toward a zone of excitation in front of a collector;
turning on a laser source to emit a laser toward the zone of excitation, such that the metal droplet is heated by the laser to generate EUV radiation;
guiding the EUV radiation, by using one or more first optics, toward a reflective mask in an exposure device; and
guiding the EUV radiation, by using one or more second optics, reflected from the reflective mask toward a multilayer photoresist stack coated substrate in the exposure device,
wherein the multilayer photoresist stack comprises:
a lower photoresist layer; and
an upper photoresist layer on the lower photoresist layer and being less reactive to hydrogen radicals than the lower photoresist layer, and wherein the upper photoresist layer comprises:
a first component having a cross-linker;
a second component having a solubility control unit, wherein the second component further comprises:
a polymer backbone; and
an intermediate bonding unit, the solubility control unit is bonded to the polymer backbone through the intermediate bonding unit, and the intermediate bonding unit and the solubility control unit collectively form the following chemical structure:
a solvent, wherein the first component and the second component are dissolved in the solvent, the solvent comprises tetramethylammonium hydroxide (TMAH), Tetrabutylammonium hydroxide (TBAH), KOH, NaOH, HCL, HF, or water, and
wherein guiding the EUV radiation, by using one or more second optics, reflected from the reflective mask toward the multilayer photoresist stack coated substrate in the exposure device is performed such that the lower photoresist layer and the upper photoresist layer are developable in a same developing steps; and
a photo acid generator (PAG) containing a cation consisting of:
Structural formula (2) and an anion selected from the group consisting of anions represented by structural formulae (3) to (10) and (12):
5 . A method for lithography patterning, comprising:
forming a first photoresist layer over a substrate;
forming a second photoresist layer over the first photoresist layer, wherein the second photoresist layer has a composition different from a composition of the first photoresist layer, and wherein:
the second photoresist layer comprises:
a solvent;
a polymer dissolved in the solvent, wherein the polymer comprises:
a first component includes a polymer backbone and a cross-linker bonded to the polymer backbone through an intermediate bonding unit, wherein a content of the cross-linker of the first component of the polymer is about 15 atomic percent (at %) to about 65 atomic percent (at %) based on a total content of the polymer; and
a photo acid generator (PAG) containing a cation consisting of:
and an anion selected from the group consisting of anions represented by structural formulae (3) to (10) and (12):
and
the polymer of the second photoresist layer further comprises:
a second component comprises a solubility control unit, the solubility control unit comprises an ester group directly bonded to a —CH 2 CH— group, the CH 2 CH group directly bonded to two ether groups, the solubility control unit is selected from the group consisting of the following chemical structures:
irradiating the first photoresist layer and the second photoresist layer with an EUV radiation;
developing the first photoresist layer and the second photoresist layer in a single developing step such that the first photoresist layer forms separated first resist segments and the second photoresist layer forms separated second resist segments; and
etching the substrate using the first photoresist layer and the second photoresist layer as an etch mask.
6 . The method of claim 5 , wherein the cross-linker is one of the following:
R2 represents a substituted or unsubstituted linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms, and m and n are integers in a range from 1 to 6.
7 . The method of claim 5 , wherein the intermediate bonding unit comprises alky group, alkene group, —S-unit, —P-unit; —P(O 2 )-unit, —C(═O)S-unit, —C(═O)O-unit, —O-unit, —N-unit, —C(—O)N-unit, —SO 2 O-unit, —SO 2 S unit, —SO-unit, —SO 2 -unit, carboxylic acid, ether, ketone, ester, or benzene unit.
8 . The method of claim 1 , wherein the second photoresist layer further comprises:
a quencher, and a content of the quencher is about 0.1 atomic percent (at %) to about 10 atomic percent (at %) based on a total content of the first component and the second component.
9 . The method of claim 1 , wherein the second photoresist layer further comprises:
a photo acid generator (PAG), and a content of the PAG is about 1 atomic percent (at %) to about 30 atomic percent (at %) based on a total content of the first component and the second component.
10 . The method of claim 1 , wherein the solvent has a boiling temperature of about 60° C. to about 280° C.
11 . The method of claim 1 , wherein the first photoresist layer has a thickness different from a thickness of the second photoresist layer.
12 . The method of claim 1 , wherein the second photoresist layer has a thickness less than a thickness of the first photoresist layer.
13 . The method of claim 5 , wherein the second photoresist layer has a thickness less than a thickness of the first photoresist layer.
14 . The method of claim 5 , wherein the first photoresist layer has a thickness different from a thickness of the second photoresist layer.
15 . The method of claim 1 , further comprising:
prior to forming the multilayer photoresist stack over the substrate, forming a carbon-rich material layer over the substrate; and
forming a silicon-rich material layer over the carbon-rich material layer.
16 . The method of claim 15 , further comprising:
after performing the developing step, performing a first etching process to the silicon-rich material layer using the separated first resist segments and separated second resist segments as an etch mask; and
performing a second etching process to the carbon-rich material layer using the silicon-rich material layer as an etch mask.
17 . The method of claim 5 , wherein the cross-linker is one of the following:
R2 represents a substituted or unsubstituted linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms, and m and n are integers in a range from 2 to 6.
18 . The method of claim 5 , wherein the solvent is amide in aqueous phase.
19 . The method of claim 5 , wherein the solvent is amine in aqueous phase.
20 . The method of claim 5 , wherein the solvent is in aqueous phase.