Abstract: A mask frame assembly includes a frame having an opening and a mask having at least two unit mask elements. Both ends of each unit mask element are fixed to the frame in a state of tension. The unit mask elements include a unit masking pattern, and overlap each other on a predetermined width to form a single mask pattern block. Each unit mask element has a recessed wall in an overlapping portion thereof so as to maintain the thickness of the mask constant at an overlap between the unit mask elements. Accordingly, the mask frame assembly reduces distortion in an evaporation pattern due to an increase in the size of a mask pattern, facilitates the adjustment of a total pitch of evaporation patterns, and prevents evaporation from occurring at undesired positions.

Abstract: A mask frame assembly used in vacuum deposition of thin films of an organic electroluminescent device. The mask frame assembly includes a frame having an opening and at least two unit masks which each have at least one unit masking pattern portion in the direction of the unit mask and two edges which are fixed to the frame under tension.