Abstract: A fabrication method for a flash memory device with a split floating gate is described. The method provides a substrate, wherein an oxide layer and a patterned sacrificial layer are sequentially formed on the substrate Ion implantation is then conducted to form source/drain regions with lightly doped source/drain regions in the substrate beside the sides of the patterned sacrificial layer using the patterned sacrificial layer as a mask. Isotropic etching is further conducted to remove a part of the patterned sacrificial layer, followed by forming two conductive spacers on the sidewalls of the patterned sacrificial layer. The patterned sacrificial layer and oxide layer that is exposed by the two conductive spacers are then removed to form two floating gates. Subsequently, a dielectric layer and a control gate are formed on the substrate.

Abstract: A fabrication method for a memory device is described. The method includes sequentially forming a pad oxide layer and a mask layer on a substrate, wherein the mask layer exposes a portion of the pad oxide layer. Thereafter, an ion implantation process is conducted to form a buried bit line in the substrate that is not covered by the mask layer. A raised bit line is then formed on the pad oxide layer above the buried bit line. The mask layer and the pad oxide layer are then removed, followed by forming a conformal gate oxide layer on the surface of the substrate and the raised bit line. A word line is further formed on the gate oxide layer.

Abstract: The present invention provides a method for fabricating a semiconductor device that can be applied in system on chip (SOC), comprising: providing a substrate with a memory cell region and a peripheral circuit region; forming a plurality of bit-lines in the memory cell region; forming a first and a second dielectric layers respectively in the memory cell region and the peripheral circuit region; and forming a plurality of gates. Next, a blanket ion implantation step is performed to form a plurality of P type LDDs in the substrate besides the gates in a PMOS device region within the peripheral circuit region, without forming an anti-punch through region in the substrate of the memory cell region. Afterwards, a plurality of spacers are formed, connected to one another. An ion implantation step is performed to form a plurality of P type source/drain regions.

Abstract: A method of scaling down device dimension using spacer to confine the buried drain implant, applicable for forming memory device such as substrate/oxide/nitride/oxide/silicon (SONOS) stacked device or nitride read only memory (NROM) device. A patterned conductive layer is used as a mask for forming a pocket doped region. A spacer is formed on a side-wall of the conductive layer. As the implantation region is confined by the side-wall, a buried drain region formed by drain implantation is reduced. Therefore, the effective channel length is not reduced due to the diffusion of the buried drain region. It is thus advantageous to scale down device dimension.

Abstract: A method of fabricating a SONOS device, in which a first silicon oxide layer, a trapping layer, and a second silicon oxide layer are formed on the substrate. Then, a mask pattern is formed over the substrate to serve as a mask in the implantation process for forming the buried bit-lines. Afterward, a portion of the mask pattern is removed to increase the gap size of the mask pattern, then a pocket ion implantation is performed to form a pocket doped region at the periphery of the buried bit-line by using the mask pattern as a mask. Subsequently, the mask pattern is removed and a thermal process is conducted using the trapping layer as a mask to form a buried bit-line oxide layer. A word-line is subsequently formed over the substrate.