Semiconductor structure and fabrication method thereof

A method for fabricating a semiconductor structure, comprising:

• providing a first substrate, and forming a drive pad on the first substrate;
• providing a second substrate, and forming a plurality of active pillars and a bit line in sequence on a side of the second substrate, wherein a side of the bit line is connected to the plurality of active pillars, and a surface of the bit line facing away from the plurality of active pillars is exposed on a surface of the second substrate;
• bonding the bit line to the drive pad correspondingly;
• thinning the second substrate from a side of the second substrate facing away from the first substrate until the plurality of active pillars are exposed;
• and
• forming a storage capacitor on sides of the plurality of active pillars facing away from the drive pad, the storage capacitor being connected to the plurality of active pillars;
• wherein:
• after the plurality of active pillars are formed and before the bit line is formed, the method further comprises:
• forming a word line material layer on side walls of the plurality of active pillars;
• and
• after the second substrate is thinned until the plurality of active pillars are exposed, and before the storage capacitor is formed on the sides of the plurality of active pillars facing away from the drive pad, the method further comprises:
• etching the word line material layer to form a word line;
• wherein the bit line extends in a first direction, the word line extends in a second direction, and the first direction intersects with the second direction.