20120620 for linux). This variant is less comparable to the previous version as it is not compatible with Windows versions older than Windows 10. You may be interested in the Parallel EasyRecovery - tool / tool package -.
References
Category:Data recovery software1. Field of the Invention
This invention generally relates to semiconductor devices and more specifically, to a method of manufacturing MOS semiconductor devices having a floating gate.
2. Description of the Related Art
A conventional MOS type semiconductor memory is proposed in which a silicon nitride film is utilized as a stopper for ion injection in order to obtain a threshold voltage in a predetermined range. In the conventional method of manufacturing a semiconductor memory, a semiconductor substrate is processed to form a field oxide film. On the field oxide film a polysilicon film, a silicon nitride film and a silicon oxide film are formed in order. A contact hole is formed by selectively etching the silicon oxide film. A polysilicon film is then selectively etched to provide a gate electrode and a source/drain region. After that, a silicon oxide film is formed all over the substrate. The silicon oxide film on the field oxide film is selectively etched. This forms a floating gate electrode by the polysilicon film and the silicon nitride film.
FIG. 1 shows a MOS type semiconductor memory cell disclosed in Japanese Patent Laid-Open Publication No. 63-100771.
In FIG. 1, reference numeral 3 indicates a field oxide film. A gate electrode 6 composed of a polysilicon film 1, a silicon nitride film 2, and a silicon oxide film 3 is formed on the field oxide film 3. A source/drain region 4 is formed in the semiconductor substrate which is provided with the field oxide film 3 and the gate electrode 6.
In the above-described prior art, the stopper for ion injection in the formation of the source/drain region in the semiconductor substrate is formed by polysilicon film, which is formed through a plurality of processes. For that reason, the time required for the production of the semiconductor device is too long.
In particular, the high integration of the MOS semiconductor memory requires the fine processing of the device. With the fine processing, the film thickness of the gate insulating film is reduced. Therefore, the capacitance of the capacitor is reduced and the characteristic of the memory cell is degraded.
In addition, a manufacturing cost is
Related links:
Yorumlar