an oxygen content of the graphene derivative is equal to or greater than about 1 wt % and equal to or less than about 10 wt % based on a total weight of the graphene derivative. 

2. The composition as claimed in claim 1, wherein the hydrophilic group is selected from a hydroxyl group, a carboxyl group, an amino group, an amido group, a nitro group, a cyano group, a polyalkyleneoxide group, and a sulfa group. 

3. The composition as claimed in claim 1, wherein the graphene derivative is obtained by oxidizing graphene. 

4. The composition as claimed in claim 1, wherein a weight average molecular weight of the graphene derivative is about 1000 to about 20000. 

5. A composition for forming a topcoat layer, the com- position comprising: 

a nonionic surfactant; 

a graphene derivative including a hydrophilic group; 

a solvent; and 

a binder including a deep-ultraviolet absorbing group, wherein: 

the graphene derivative is present in an amount of about 0.5 to about 10 wt % based on a total weight of the composition, 

the binder is present in an amount about 0.01 to about 10 wt % based on a total weight of the composition, and 

an oxygen content of the graphene derivative is equal to or greater than about 1 wt % and equal to or less than about 10 wt % based on a total weight of the graphene derivative. 

6. The composition as claimed in claim 5, wherein an amount of the nonionic surfactant is about 0.01 to about 0.5 wt % based on a total weight of the composition. 

7. A pattern formation method, comprising: 

disposing a resist composition on a substrate, to form a resist layer; 

coating the resist layer with a topcoat composition for forming a topcoat layer, the topcoat composition including: 

a graphene derivative including a hydrophilic group; and 

a solvent; 

heating the topcoat composition to harden the topcoat composition; 

subjecting the resist layer to exposure using extreme ultraviolet light; and 

developing exposed resist layer with an alkali aqueous solution. 

8. The pattern formation method as claimed in claim 7, wherein the extreme ultraviolet light has a wavelength in a range of about 5 to about 20 nm. 

9. The pattern formation method as claimed in claim 8, wherein the topcoat composition has a thickness of about 1 to about 100 nm on the resist layer. 

10. The pattern formation method as claimed in claim 7, wherein the heating step is carried out at a temperature of about 25 to about 150° C. 

* * * * * 

