Memory and forming method thereof

Abstract

The invention provides a memory and a forming method thereof. A bit line and an insulating line are used for defining a first grid array, after the bit lines and the insulating lines are formed, the isolation layer is used for further defining the second lattice array corresponding to the first lattice array, so that the first lattice array and the second lattice array can be combined to define the node contact window, and then the node contact structure can be filled in the node contact window in a self-aligned mode. Therefore, according to the memory and the forming method thereof, when a node contact structure is prepared, a graphical process does not need to be executed on a conductive material used for forming the node contact structure, thus, the etching process in the patterning process of the conductive material with high hardness can be omitted, the pattern precision of the formed node contact structure can be improved, polymers can be prevented from being generated, and the polymers are prevented from being attached to the node contact structure.

Description

technical field [0001] The invention relates to the technical field of semiconductors, in particular to a memory and a forming method thereof. Background technique [0002] Memory, such as dynamic random access memory (Dynamic Random Access Memory, DRAM), which generally includes a storage capacitor and a storage transistor electrically connected to the storage capacitor, the storage capacitor is used to store charges representing stored information, and the storage transistor The storage capacitor can be electrically connected through a node contact structure. [0003] Wherein, the preparation method of the node contact structure generally includes: [0004] Firstly, depositing a layer of conductive material on the substrate, and forming a mask layer on the layer of conductive material, so as to use the mask layer to define the pattern of the node contact structure; [0005] Next, etching the conductive material layer using the mask layer as a mask, so as to copy the patt...

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Problems solved by technology

[0007] However, it should be noted that, in the above-mentioned preparation method, on the one hand, the hardness of the conductive material used to form the node contact structure is usually relatively high, so that the etching rate of the conductive material layer is relatively low during the etching process. low, and will also produce a large lateral undercutting phenomenon, which will affect the morphology of the formed node contact structure; on the other hand, when the mask layer is used as a mask to etch the conductive material layer, it is often still By-products such as polymers will be produced, which are easily attached to the surface of the node contact structure, which will lead to an increase in the contact resistance between the formed node contact structure and the subsequently formed storage capacitor

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