US 11,815,809 B2
Extreme ultraviolet mask absorber materials
Shuwei Liu, Singapore (SG); Shiyu Liu, Singapore (SG); Azeddine Zerrade, Singapore (SG); and Vibhu Jindal, San Jose, CA (US)
Assigned to Applied Materials, Inc., Santa Clara, CA (US)
Filed by Applied Materials, Inc., Santa Clara, CA (US)
Filed on Mar. 23, 2021, as Appl. No. 17/209,707.
Claims priority of provisional application 63/000,724, filed on Mar. 27, 2020.
Prior Publication US 2021/0302826 A1, Sep. 30, 2021
Int. Cl. G03F 1/58 (2012.01); G03F 1/24 (2012.01)
CPC G03F 1/58 (2013.01) [G03F 1/24 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An extreme ultraviolet (EUV) mask blank comprising:
a substrate;
a multilayer stack which reflects EUV radiation, the multilayer stack comprising a plurality of reflective layer pairs;
a capping layer on the multilayer stack; and
an absorber on the capping layer, the absorber comprising a first layer on the capping layer, the first layer selected from the group consisting of Mo, Nb, V, alloys of Mo, Nb and V, oxides of Mo, oxides of Nb, oxides of V, nitrides of Mo, nitrides of Nb and nitrides of V and a second layer on the first layer, the second layer an alloy selected from the group consisting of TaSb, CSb, SbN, TaNi, TaCu and TaRu, the absorber comprising the first layer and second layer providing a tunable phase shift and reflectance.