Abstract:
The present invention relates to a non-volatile memory device having conductive sidewall spacers and a method for fabricating the same. The non-volatile memory device includes: a substrate; a gate insulation layer formed on the substrate; a gate structure formed on the gate insulation layer; a pair of sidewall spacers formed on sidewalls of the gate structure; a pair of conductive sidewall spacers for trapping/detrapping charges formed on the pair of sidewall spacers; a pair of lightly doped drain regions formed in the substrate disposed beneath the sidewalls of the gate structure; and a pair of source/drain regions formed in the substrate disposed beneath edge portions of the pair of conductive sidewall spacers.
Abstract:
Disclosed are a memory device and a method for fabricating the same. The memory device includes: a substrate provided with a trench; a bit line contact junction formed beneath the trench; a plurality of storage node contact junctions formed outside the trench; and a plurality of gate structures each being formed on the substrate disposed between the bit line contact junction and one of the storage node contact junctions. Each sidewall of the trench becomes a part of the individual channels and thus, channel lengths of the transistors in the cell region become elongated. Accordingly, the storage node contact junctions have a decreased level of leakage currents, thereby increasing data retention time.
Abstract:
The present invention relates to a method for fabricating a gate electrode of a semiconductor device with a double hard mask capable of preventing an abnormal oxidation of a metal layer included in the gate electrode and suppressing stress generation. The method includes the steps of: forming a gate insulation layer on a substrate; forming a gate layer structure containing at least a metal layer on the gate insulation layer; forming a hard mask oxide layer on the gate layer structure at a temperature lower than an oxidation temperature of the metal layer; forming a hard mask nitride layer on the hard mask oxide layer; patterning the hard mask oxide layer and the hard mask nitride layer as a double hard mask for forming the gate electrode; and forming the gate electrode by etching the gate layer structure with use of the double hard mask as an etch mask.
Abstract:
Disclosed is a method for fabricating a semiconductor device with a dual gate dielectric structure. The method includes the steps of: sequentially forming a first oxide layer, a nitride layer and a second oxide layer on a substrate provided with a cell region for the NVDRAM and a peripheral circuit region for a logic circuit; forming a mask on the cell region; performing a first wet etching process by using the mask as an etch barrier to remove the second oxide layer formed in the peripheral circuit region; performing a second wet etching process by using the second oxide layer remaining in the cell region as an etch barrier to remove the nitride layer formed in the peripheral circuit region; forming a third oxide layer on the first oxide layer remaining in the peripheral circuit region; and forming a gate electrode on the second oxide layer and the third oxide layer.
Abstract:
The present invention relates to a method of forming a damascene gate electrode of highly integrated MOS transistor capable of easily removing a dummy polysilicon layer. The disclosed comprises the steps of forming a dummy gate insulating layer and a polysilicon layer for a dummy gate on a wafer; forming an interlayer insulating layer on the wafer; polishing the interlayer insulating layer to expose a top surface of the dummy polysilicon layer; and wet etching the exposed dummy polysilicon layer using a spin etching process.
Abstract:
A method of forming dual-metal gates in a semiconductor device, including the steps of providing a semiconductor substrate having a PMOS area and an NMOS area wherein dummy gates are formed in the PMOS and NMOS areas respectively, forming an insulating interlayer on the semiconductor substrate so as to cover the dummy gates, polishing the insulating interlayer until the dummy gates are exposed, forming a first groove defining a first metal gate area by selectively removing one of the dummy gates formed in the PMOS and NMOS areas, forming a first gate insulating layer and a first metal layer on an entire area of the semiconductor substrate including the first groove successively, forming a first metal gate in the first groove by etching the first metal layer and first gate insulating layer until the insulating interlayer is exposed, forming a second groove defining a second metal gate area by removing the remaining dummy gate, forming a second gate insulating layer and a second metal layer on the entire area of the semiconductor substrate including the second groove, and forming a second metal gate in the second groove by etching the second metal layer and second gate insulating layer until the insulating interlayer is exposed.
Abstract:
The MOSFET fabrication method allows application of a self-aligned contact (SAC) process while maintaining a metal gate, such as a tungsten gate, to have a uniform thickness. The process involves forming a metal oxide film during the formation of a metal gate structure of the MOSFET device. The metal oxide film is formed by subjecting the gate structure through a rapid thermal oxidation (RTO) treatment and then to an N2O plasma treatment. The treatments allow the thickness of the metal oxide to be precisely controlled. The metal oxide acts as an insulator, which prevents electrical shorts between the gate structure and a contact plug even if a misalignment of occurs during the SAC process. This is an improvement from the conventional practice of separately forming a SAC barrier film after the formation of the metal gate structure and thus saves money, time, and increases reliability and productivity. Also the performance characteristics of the device is enhanced.
Abstract:
A method of forming a gate electrode with a titanium polycide which can prevent particle creation and abnormal oxidation of the gate electrode, is disclosed. In the present invention, a gate oxidation process is performed after implanting Si ions into the side wall or overall surface of the titanium silicide layer, thereby preventing abnormal oxidation of the titanium silicide during the gate oxidation process. Furthermore, a titanium silicide layer is deposited to a low mole ratio of Si/Ti, thereby minimizing particle creation.
Abstract:
A field oxide formation method involving a primary field oxidation, which is carried out at a predetermined low temperature to form a field oxide film having a thickness smaller than a target thickness, and a secondary field oxidation, which is carried out at a higher temperature capable of relatively reducing the occurrence of a field thinning phenomenon, to form the remaining thickness portion of the target field oxide film. The field thinning phenomenon involved in a field oxidation is reduced. The characteristics of a finally produced gate oxide film is also improved. Consequently, the throughput and reliability of semiconductor devices having gate oxide films are improved.
Abstract:
A method for forming a field oxide film for element isolation of a structure extending deeply in the substrate and having a step of small height, thereby exhibiting a low topology and a reduced bird's beak. The method includes the steps of forming a pattern of a mask material film for an oxidation prevention on a semiconductor substrate, locally forming an oxide film on a predetermined surface portion of the semiconductor substrate by use of an oxidation using the pattern as a mask, and removing the oxide film, thereby etching the predetermined surface portion of the semiconductor substrate while forming an undercut at a region defined beneath a side wall of the mask material film pattern, forming a lateral oxidation prevention film on the undercut disposed beneath the side wall of the mask material film pattern, and forming an oxide film for an element isolation, by use of an oxidation, on a portion of the semiconductor substrate exposed upon etching the predetermined surface portion of the semiconductor substrate.