End effector assembly for clean/dirty substrate handling

An end effector comprising:

• a first substrate support pad defining a first height;
• a second substrate support pad defining a second height that is less than the first height;
• a third substrate support pad defining a third height that is greater than the second height;
• a fourth substrate support pad defining a fourth height that is less than the third height;
• a fifth substrate support pad defining a fifth height that is greater than the fourth height;
• a sixth substrate support pad defining a sixth height that is greater than the fourth height;
• and
• a seventh substrate support pad defining a seventh height that is less than the sixth height,
• wherein the first, third, fourth, and seventh substrate support pads define a first circle having a first diameter and a first central axis,
• wherein the second, fifth, and sixth substrate support pads define a second circle having a second diameter and a second central axis, and
• wherein the first diameter is equal to the second diameter and the first central axis is offset from the second central axis.