Mask assembly, method of manufacturing mask assembly, and method of manufacturing display apparatus

A method of manufacturing a display apparatus, the method comprising:

• preparing a mask assembly;
• arranging a display substrate to face the mask assembly;
• and
• passing a deposition material through the mask assembly and depositing the deposition material on the display substrate, the deposition material being supplied from a deposition source, wherein
• the preparing of the mask assembly includes:
• preparing a mask frame including an opening area;
• forming an opening of a first group in a first area of a center of a mask sheet;
• tensioning and fixing the mask sheet to the mask frame;
• and
• forming an opening of a second group in a second area of the mask sheet, and
• the second area surrounds the first area.

A mask assembly comprising:

• a mask frame including an opening area;
• and
• a mask sheet disposed within the opening area, wherein
• the mask sheet includes:
• a first area in a center, having an opening of a first group;
• and
• a second area having an opening of a second group and surrounding the first area,
• the first area has a first inclined surface in a thickness direction in a circumference of the opening of the first group,
• the second area has a second inclined surface in the thickness direction in a circumference of the opening of the second group, and
• an inclined angle of the first inclined surface is different from an inclined angle of the second inclined surface.