Semiconductor structure and preparation method thereof

Abstract

The invention provides a semiconductor structure and a preparation method thereof. The method comprises the steps that: a wafer group is provided, the wafer group comprises a first wafer to an Nth wafer, wherein N is an integer greater than or equal to 3; a kth barrier layer is embedded in a partial region of the front surface of the kth wafer, wherein k is an integer greater than or equal to 3 and less than or equal to N; a first barrier layer isembedded in a partial region of the back surface of the first wafer; after a k2th barrier layer is formed, the front face of the k2th wafer and the back face of the k1th wafer are bonded, k2 and satisfy the relational expression that k2-k1=1, wherein k2 is an integer larger than or equal to 3 and smaller than or equal to N; after the first barrier layer is formed, the back surface of the first wafer and the front surface of the second wafer are bonded; and the first wafer to the Nth wafer are etched from the front surface of the first wafer by taking the first barrier layer and the third barrier layer to the Nth barrier layer as masks so as to form a multi-step groove in the first wafer to the Nth wafer. The bottom of the multi-step groove is flat, the appearance of the multi-step groove is good, and the precision of the multi-step groove is high.

Description

technical field [0001] The invention relates to the technical field of semiconductors, in particular to a semiconductor structure and a preparation method thereof. Background technique [0002] In the semiconductor manufacturing process, it is usually necessary to process multi-step grooves in some special semiconductor structures. For example, in the field of electromagnetic wave transmission, the electromagnetic wave is sent from the transmitter through the intermediate transmission structure and then received by the receiver. In the case of millimeter wave transmission, an intermediate transmission structure with a multi-step groove structure is often used. [0003] In the process of preparing the multi-step groove structure on the wafer, because the multi-step groove has grooves of different depths, the existing technology usually adopts multiple photolithography and etching processes to form it, but due to the characteristics of the etching process itself , the depth o...

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