The invention discloses a double-sided semi-embedded packaging substrate and a
processing method thereof, and the
processing method comprises the steps: carrying out the N times of double-sided circuit manufacturing and the N-1 times of double-sided layer adding of a multi-layer substrate alternately, and obtaining an operation board with two groups of symmetrical circuit structures; the circuit structure is provided with an outer circuit layer and (N-1) inner circuit
layers which are communicated with each other, and the inner circuit layer located on the innermost side is provided with a bonding pad. Performing
laser groove burning on the working board, and
processing a blind groove which is provided with an opening at the outer circuit layer and takes the other inner circuit layer adjacent to the innermost inner circuit layer as the groove bottom locally on each group of circuit structure; removing the
copper foil on the bottom of the blind groove; the bonding pads are completely exposed in the blind grooves corresponding to the bonding pads, the blind grooves in the two sets of circuit structures are communicated, and a through groove structure is obtained; and cleaning the surface of the bonding pad to obtain the double-sided semi-embedded packaging substrate. The processing method is simple and reasonable, the
processing cost is low, the processing efficiency is high, and the reliability of the obtained double-sided semi-embedded packaging substrate is very high.