Semiconductor contact structure, memory structure and preparation method

Abstract

The invention provides a semiconductor contact structure, a memory structure and a preparation method thereof. The preparation method of the memory structure comprises the following steps: 1) providing a semiconductor substrate; 2) a plurality of word lines are formed at parallel intervals in that semiconductor substrate; 3) bury a plurality of bit lines arrange at parallel intervals on that semiconductor substrate; 4) for a first conductive layer on that bit line; 5) for a second conductive material layer on that first conductive lay; 6) etch that second conductive material layer to form a second conductive lay by adopting a back etching process; 7) for a reconfiguration mask layer on that upper surface of the structure obtain in the step 6); Forming connection holes in the reconfigured mask layer; 8) for a connection pad material layer in that connection via hole and on the upper surface of the reconfigured mask layer; 9) etching the connection pad material lay to form a connection pad by adopting a etching-back process. The invention can improve the contact resistance of the connection pad and the bridging tolerance between the connection pads.

Description

technical field [0001] The invention belongs to the technical field of semiconductor integrated circuit manufacturing, and in particular relates to a semiconductor contact structure, a memory structure and a preparation method thereof. Background technique [0002] As the manufacturing process of Dynamic Random Access Memory (DRAM for short: DRAM) becomes more and more refined, it becomes more and more difficult to make the pattern forming the basis of unit nodes in the chip, especially in order to make the basic tolerance of storage unit nodes and unit contact nodes Generally, connection pads are required, but this makes the contact resistance of the connection pads and the bridging tolerance between the connection pads more fragile. The main reason is that in the prior art, the storage unit node and the connection pad layer are generally formed by depositing the same conductive material layer, that is, the connection pad layer is formed at the same time as the storage unit...

AI Technical Summary

Problems solved by technology

However, when etching the connection pad layer to form an opening in the connection pad layer to form the connection pad, due to the existence of etching by-products, or the opening is too small, or the opening Etching dislocation can easily lead to a short circuit connection between the adjacent connecting pads that are electrically connected to the storage unit node 1'; and in order to avoid the electrical connection between adjacent connecting pads, it is necessary to etch and remove enough The connection pad layer, so that the opening formed by etching is large enough, so that there is a sufficient gap between the adjacent connection pads, however, although this can improve the problem of ..., it will lead to a connection pad layer Excessive consumption makes the width of the connection between the connection pad and the storage unit node very small, and even disconnects the connection pad from the storage unit node, which will undoubtedly significantly increase the The contact resistance with the memory cell node, which in turn affects the performance of the memory structure

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