Abstract:
The present invention relates to a method for sealing a nonvolatile memory device, characterized in that to comprise the following steps of: a) defining a nonvolatile memory cell (20), being composed by the overlap of a tunnel oxide (3), of a floating gate (1), of an interpoly dielectric (2), and of a control gate (4); b) deposing a silicon oxide layer (11) by a CVD (Chemical Vapor Deposition) at a temperature lower than 1000 °C on said control gate (4); c) densifing said silicon oxide layer (11) by a further thermal treatment (13). (Figure 5).
Abstract:
The invention relates to a process for manufacturing an interpoly dielectric layer (2) for non-volatile memory cells of a semiconductor device with an interpoly dielectric layer (2). The process begins with forming the tunnel oxide (3), and hence the amorphous or polycrystalline silicon layer (4), using conventional techniques. After the amorphous or polycrystalline silicon layer (4) is surface cleansed and passivated, the surface of the polycrystalline layer (4) is :nitrided directly by using radical nitrogen. This is followed by the formation of the interpoly dielectric, either as an ONO layer or a single silicon layer, by means of the CVD technique. Masking to define the floating gate may be performed immediately before or after the direct nitridation step is carried out. The equivalent electrical thickness of the interpoly dielectric, obtained by combining the nitride oxide layer and by the following dielectric, doesn't exceed 130 Angstroms in either the ONO layer or the single silicon layer embodiment.
Abstract:
The invention is a process for manufacturing a non-volatile memory cell having at least one gate region (10), the process comprising the steps of:
depositing a first dielectric layer onto a semiconductor substrate; depositing a first semiconductor layer (1) onto the first dielectric layer to form a floating gate region of the memory cell; and defining said floating gate region of the memory cell in the first semiconductor layer (1).
Advantageously in the invention, the manufacturing process further includes the step of:
depositing a second dielectric layer (5) onto the first conductive layer (1), the dielectric layer (5) having a higher dielectric constant than 10.
Also disclosed is a memory cell, which is integrated in a semiconductor substrate and has a gate region (10) that comprises a dielectric layer (5) formed over a first conductive layer (1) and having a higher dielectric constant than 10.