Photoresist, method of manufacturing a semiconductor device and method of extreme ultraviolet lithography

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):

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 —CH2CH— group, the CH2CH 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.