Method for manufacturing magnetic memory chip device
A method for manufacturing a magnetic memory chip device comprises the steps of: writing information in each of a plurality of magnetic memory chips formed on a silicon wafer; adhering a high magnetic permeability plate on a back face of the silicon wafer after writing information, the high magnetic permeability plate having a higher magnetic permeability than silicon and having a thickness of 50 μm or more; dicing the silicon wafer into respective magnetic memory chips after adhering the high magnetic permeability plate.
1. A method for manufacturing a magnetic memory chip device comprising the steps of:
preparing a silicon wafer having a plurality of magnetic memory chips, the silicon wafer having a predetermined thickness;
writing information in each of the plurality of magnetic memory chips of the silicon wafer;
after the step of writing information, back-grinding the silicon wafer to reduce the predetermined thickness of the silicon wafer;
after the step of back-grinding, adhering a high magnetic permeability plate on a back face of the silicon wafer having the reduced thickness by the back-grinding, the high magnetic permeability plate having a higher magnetic permeability than silicon and having a thickness of 50 μm or more;
dicing the silicon wafer into respective magnetic memory chips after adhering the high magnetic permeability plate.
2. The method for manufacturing a magnetic memory chip device as claimed in claim 1 , wherein the thickness of the high magnetic permeability plate is 100 μm or more.