Dressing apparatus and substrate holding apparatus

A dressing apparatus for dressing a polishing surface of a polishing table for polishing a surface of a substrate, said dressing apparatus comprising:

• a dresser body;
• a dresser plate disposed vertically movably with respect to said dresser body;
• a dressing member supported by said dresser plate;
• a hermetically sealed chamber between said dresser body and said dresser plate, at least part of said hermetically sealed chamber being defined by an elastic membrane;
• a fluid supply source for supplying a fluid under a positive pressure or a negative pressure to said hermetically sealed chamber to control a dressing load;
• a fluid passage interconnecting said hermetically sealed chamber and said fluid supply source;
• and
• a flowmeter for measuring a flow rate in said fluid passage so as to detect a leakage from said hermetically sealed chamber;
• wherein said flowmeter has a threshold for generating an alarm signal or a fault signal.

A dressing apparatus for dressing a polishing surface of a polishing table for polishing a surface of a substrate, said dressing apparatus comprising:

• a dresser body;
• a dresser plate disposed vertically movably with respect to said dresser body;
• a dressing member supported by said dresser plate;
• hermetically sealed chambers between said dresser body and said dresser plate, at least part of each of said hermetically sealed chambers being defined by an elastic membrane;
• a fluid supply source for supplying a fluid under a positive pressure or a negative pressure to each of said hermetically sealed chambers to control a dressing load;
• and
• fluid passages respectively interconnecting said hermetically sealed chambers and said fluid supply source,
• wherein said hermetically sealed chamber is defined by said elastic member comprising a tubular resilient membrane and a disk-shaped plate mounted on an end of said tubular resilient membrane, said disk-shaped plate having a constant pressure-bearing area for applying the positive pressure or the negative pressure of the fluid.

A dressing apparatus for dressing a polishing surface of a polishing table for polishing a surface of a substrate, said dressing apparatus comprising:

• a dresser body;
• a dresser plate disposed vertically movably with respect to said dresser body;
• a dressing member supported by said dresser plate;
• hermetically sealed chambers between said dresser body and said dresser plate, at least part of each of said hermetically sealed chambers being defined by an elastic membrane;
• a fluid supply source for supplying a fluid under a positive pressure or a negative pressure to each of said hermetically sealed chambers to control a dressing load;
• fluid passages respectively interconnecting said hermetically sealed chambers and said fluid supply source;
• and
• flowmeters disposed in said fluid passages, respectively, for measuring flow rates in said fluid passages, respectively, to detect leakage from said hermetically sealed chambers, respectively;
• wherein said flowmeters each have an individual threshold for generating an alarm signal or a fault signal.