The invention relates to a manufacturing method of a multilayer pre-plastic
package structure of a fine-engraved
metal lead frame. The manufacturing method comprises the following steps: step 1, designing a pattern of the
metal lead frame; 2, preparing a plate before manufacturing the
metal lead frame; 3, positioning holes are manufactured before the metal lead frame is manufactured; 4,
engraving a pattern on the back surface of the metal lead frame plate; 5,
processing burrs on the back surface of the metal lead frame plate; sixthly,
plastic packaging is conducted on the back face of the metal lead frame plate; 7,
engraving a pattern on the front surface of the metal lead frame plate; 8,
processing burrs on the front surface of the metal lead frame plate; ninthly, conducting
plastic packaging on the front face of the metal lead frame plate; 10,
electroplating the
surface layer of the metal lead frame; and 11, cleaning the
surface layer of the metal lead frame, baking,
drying and packaging. The production efficiency and the manufacturing precision are improved, and the production and manufacturing cost and the environmental
pollution are reduced.