Self-aligning contact window and its making method

Abstract

The invention provides a manufacturing method for a self aligned contact window, including the following steps that: a substrate on which a plurality of NAND type storage unit lines are formed is provided, and the NAND type storage unit lines comprise drain regions; an interlayer dielectric layer is formed on the substrate for covering the NAND type storage unit lines; the interlayer dielectric layer is patternized for forming a plurality of openings where the drain regions are exposed; the selective silicon growth process is carried out, thereby a material layer is formed on the drain regions which are exposed by the openings; and a metallic layer is formed on the material layer for filling in the openings.

Description

technical field [0001] The invention relates to a semiconductor process, and in particular to a self-aligned contact window and a manufacturing method thereof. Background technique [0002] Flash storage devices have been widely used in personal computers and electronic devices because they can store, read, and erase data multiple times, and the stored data will not disappear after power failure. A non-volatile memory element. [0003] A typical flash memory device uses doped polysilicon to make a floating gate (Floating Gate) and a control gate (Control Gate). Moreover, the control gate is directly disposed on the floating gate, the floating gate and the control gate are separated by an inter-gate dielectric layer, and the floating gate and the substrate are separated by a tunnel dielectric layer (that is, so-called stacked gate flash memory). [0004] On the other hand, flash memory arrays commonly used in the industry include NOR array structures and NAND array structu...

AI Technical Summary

Problems solved by technology

However, when the device size is reduced, the bit line contact window 106 may be shifted due to process variation, and the bit line contact window 106 will be in contact with the substrate 100, such as the circled portion 108, causing junction leakage current (Junction Leakage) )The phenomenon

In addition, using polysilicon as the material for filling the opening of the bit line contact window will increase the resistance value of the bit line contact window and affect the operating performance of the device.

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