| 主权项 |
1. An apparatus for selectively etching an encapsulant forming a package of resinous material around an electronic device comprising:
a source of etchant solution; an etching assembly including an etch plate and a movable cover, the etch plate and the cover forming an etch chamber; an etch head supported by the etch plate, wherein an electronic device package is mountable in the chamber on the etch head; a conductive electrode in electrical contact with package leads of the electronic device package to apply a first voltage to the package leads of the electronic device; a first pump configured to pump a first quantity of the etchant solution from the source into the etch head, the etchant solution being electrically biased to a second voltage different from the first voltage; a heat exchanger in flow connection with the source of etchant solution and the etch head, the heat exchanger being configured to adjust the temperature of the etchant solution flowing through the heat exchanger to the etch head; and an etchant cooling system in contact with the heat exchanger, the etchant cooling system, when activated, adjusts the temperature of the etchant solution flowing through the heat exchanger to a temperature below the ambient temperature, wherein an etch cavity is formed on an exterior surface of the electronic device package by reaction of a cooled etchant solution with the resinous material, and when the etchant solution has etched through an exterior surface of the electronic device package, the conductive bond wires of the electronic device is prevented from being etched by the applied first voltage. |
