Flash memory structure

Abstract

The invention provides a flash memory structure, which comprises a semiconductor substrate, a tunneling oxide layer, floating gates, an insulating layer, control gates, an oxide layer and nitrides. A plurality of ion doping areas are arranged in the semiconductor substrate, and each area is respectively used as a source electrode or a drain electrode; the tunneling oxide layer is formed on the surface of the substrate; the floating gates are arranged between the source electrode and the drain electrode and are superposed above the tunneling oxide layer; the insulating layer is arranged on the upper surface of the floating gates; the control gates are superposed on the surface of the insulating layer; the oxide layer is deposited on a side wall formed by superposing the floating gates, the isolating layer and the control gates, and the upper surface of the control gate; and the nitrides are deposited on the side wall of the oxide layer. Compared with the prior art, the flash memory structure provided by the invention uses the ON medium structure to replace the ONO medium structure in prior art, which improves the insulating property of the thickened nitrides, effectively overcomes the problem that the medium structure is thinned caused by removing the medium structure in subsequent etch process, greatly prolongs the holding time of the charges in the floating gate, and avoids the loss of the data.

Description

technical field [0001] The invention relates to a conductor device structure, in particular to a nonvolatile semiconductor storage structure. Background technique [0002] Memory is used to store large amounts of digital information, and according to surveys, memory transactions account for about 30% of semiconductor transactions worldwide. Over the years, the advancement of process technology and the increase of market demand have led to more and more high-density various types of memory, such as RAM (random access memory), DRAM (dynamic random access memory), ROM (read-only memory), EPROM (erasable In addition to programmable read-only memory), FLASH (flash memory) and FRAM (ferroelectric memory) and so on. Among them, flash memory, ie FLASH, has become the mainstream of non-volatile semiconductor storage technology. FLASH can not only program, erase and read data by electrical methods, but also retain data during power interruption, and has the advantages of fast access...

AI Technical Summary

Problems solved by technology

[0005] Since the existing ONO insulating dielectric structure will etch away part of the second oxide layer 8 during the subsequent etching process, and the etched thickness is difficult to control, the thickness of the ONO insulating dielectric structure is reduced, so it remains The charge in the floating gate 3 is easy to escape, resulting in the loss of data stored in the flash memory

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