The invention discloses a
laser unsealing method. The method includes the steps that positions and depths of all elements and a
chip in a plastic
package device are positioned to obtain size, position and depth information of the elements and the
chip in the device; according to the information, a preset unsealing area of the plastic
package device is determined for unsealing and positioning;
laser ablation is conducted on the plastic
package device in a cross filling mode to remove molding materials on the surface of the plastic package device, so that inner
lead bonding wires are just exposed out of a
chip area,
tin-lead
welding points are just exposed near a
resistor and a
capacitor, and
inductance is just exposed near an
inductor. Acidic liquid is adopted to corrode a molding compound covering the chip till the chip is exposed. The method can well solve the problem that a traditional method can not unseal a plastic mixed
integrated circuit easily, and effectively increases the unsealing success rate of the plastic package device.