Method for cleaning substrate, method for manufacturing photomask and method for cleaning photomask

A method, comprising:

• receiving a substrate having a hard mask disposed thereover;
• forming a patterned photoresist over the hard mask;
• patterning the hard mask using the patterned photoresist as a mask;
• and
• removing the patterned photoresist, comprising:
• oxidizing organic materials over the substrate;
• applying an alkaline solution onto the patterned photoresist after oxidizing the organic materials over the substrate;
• and
• removing the patterned photoresist by mechanical impact.

A method comprising:

• forming a sacrificial layer over a substrate;
• forming a polymeric material layer over the sacrificial layer;
• applying an ozonated deionized water over the polymeric material layer;
• applying tetramethylammonium hydroxide (TMAH) over the polymeric material layer subsequent to applying the ozonated deionized water, thereby altering molecular bonding of polymeric material layer;
• and
• providing mechanical impact to the polymeric material layer above of the substrate, wherein a portion of a top surface of the sacrificial layer is exposed subsequent to the mechanical impact.