Method of placing protective member on workpiece
A method of placing a protective member on a workpiece includes a sheet producing step of heating a plate-shaped thermoplastic resin to soften or melt the same while gripping and pulling outer edges of the thermoplastic resin in at least four directions to produce a sheet-like protective member, and after the sheet producing step, an integrating step of heating and bringing the sheet-like protective member into intimate contact with the workpiece to integrate the workpiece and the protective member with each other.
1. A method of placing a protective member on a semiconductor wafer, comprising:
a sheet producing step of heating a plate-shaped thermoplastic resin to soften or melt the plate-shaped thermoplastic resin while gripping, with a plurality of grippers, and pulling outer edges of the thermoplastic resin in at least four directions within a plane which is parallel to a face side of the semiconductor wafer to produce a sheet-like protective member; and
after the sheet producing step, an integrating step of heating and bringing the sheet-like protective member into intimate contact with the semiconductor wafer to integrate the semiconductor wafer and the protective member with each other.
2. The method of placing a protective member on the semiconductor wafer according to claim 1 , wherein the sheet producing step includes a step of adjusting a thickness of the protective member by controlling a pulled distance by which the outer edges of the thermoplastic resin are pulled.
3. The method of placing a protective member on the semiconductor wafer according to claim 1 , wherein each of the plurality of grippers has a first gripping member which supports a lower surface of the outer edge of the thermoplastic resin and a second gripping member which is attached to the first gripping member so as to be movable relatively to the first gripping member.
4. The method of placing a protective member on the semiconductor wafer according to claim 3 , wherein the second gripping member is movable between an open position that is spaced upwardly from the outer edge of the thermoplastic resin and a gripping position in which the second gripping member presses downwardly on the outer edge of the thermoplastic resin, thereby gripping the outer edge of the thermoplastic resin between the second gripping member and the first gripping member.
5. The method of placing a protective member on the semiconductor wafer according to claim 4 , wherein each of the plurality of grippers includes a gripper actuator which causes the gripper to move between the open position and the gripping position, the gripper actuator including an air cylinder which moves the second gripping member.
6. The method of placing a protective member on the semiconductor wafer according to claim 5 , wherein the gripper actuator includes a spring disposed between the air cylinder and the second gripping member.
7. The method of placing a protective member on the semiconductor wafer according to claim 1 , wherein a pantograph mechanism is connected to the grippers for expanding and contracting the grippers while keeping the grippers uniformly spaced apart.
8. The method of placing a protective member on the semiconductor wafer according to claim 7 , wherein a pair of pantograph actuators are disposed on opposite sides of the pantograph mechanism for actuating the pantograph mechanism.
9. The method of placing a protective member on the semiconductor wafer according to claim 1 , wherein the grippers are not spaced apart as the thermoplastic resin is pulled.