Circuit board and fabrication method thereof, and electronic device

A circuit board, comprising:

• a main board, wherein the main board is provided with a blind cavity;
• a daughter board, wherein the daughter board is disposed in the blind cavity, and a daughter board trace is provided in the daughter board;
• and
• a build-up board, wherein the build-up board is disposed on surfaces of the main board and the daughter board;
• the build-up board comprises a build-up structure containing a plurality of layers;
• the build-up board is provided with a first chip region, a second chip region, and an interconnection region located between the first chip region and the second chip region;
• and the interconnection region covers a surface of the daughter board;
• and
• a plurality of interconnection traces are provided in the interconnection region;
• each interconnection trace comprises:
• a first horizontal trace and a second horizontal trace disposed on a same layer of the build-up structure, a first vertical trace disposed in the build-up board and configured to connect the first horizontal trace and the daughter board trace, and a second vertical trace disposed in the build-up board and configured to connect the second horizontal trace and the daughter board trace;
• a first trace configured to connect the first horizontal trace and a first chip is provided in the first chip region, and a second trace configured to connect the second horizontal trace and a second chip is provided in the second chip region.