Semiconductor structure and preparation method thereof, and preparation method of semiconductor device

The invention relates to a semiconductor structure and a preparation method thereof, and a preparation method of a semiconductor device. According to the semiconductor structure, an epitaxial transmission layer comprises device regions and test regions which are alternately arranged; the to-be-tested structure is at least partially located in the device region; the testing structure is at least partially located in the testing area, and a gap is formed between the testing structure and the to-be-tested structure; the source electrode of the to-be-tested structure is used for receiving a first excitation signal and a first detection signal, and the test electrode of the test structure is used for receiving a second excitation signal and a second detection signal; under the action of the first excitation signal and the second excitation signal, the test structure transmits the second excitation signal to the source electrode of the to-be-tested structure through the epitaxial transmission layer so as to form a