摘要:
A method for manufacturing a split-gate flash memory cell, comprising the steps of forming an active region on a semiconductor substrate; forming a buffer layer on the semiconductor substrate; forming a first dielectric layer on the buffer layer; removing part of the first dielectric layer; defining an opening; removing the buffer layer within the opening; forming a gate insulating layer and floating gates; forming a source region in the semiconductor substrate; depositing a conformal second dielectric layer on the opening; removing the buffer layer outside the first dielectric layer and the floating gates; and forming an oxide layer and control gates.
摘要:
A method for manufacturing a split-gate flash memory cell, comprising the steps of forming an active region on a semiconductor substrate; forming a buffer layer on the semiconductor substrate; forming a first dielectric layer on the buffer layer; removing part of the first dielectric layer; defining an opening; removing the buffer layer within the opening; forming a gate insulating layer and floating gates; forming a source region in the semiconductor substrate; depositing a conformal second dielectric layer on the opening; removing the buffer layer outside the first dielectric layer and the floating gates; and forming an oxide layer and control gates.
摘要:
A method of fabricating a flash memory cell. The method includes the steps of providing a semiconductor substrate; forming a first gate insulating layer; forming a first conductive layer on the first gate insulating layer; forming a floating gate insulating layer; forming a source region by implanting impurity ions into the substrate; forming a second insulating layer; forming a floating gate region; forming a third insulating; forming a second conductive layer on the third insulating layer; forming a fourth insulating layer on the second conductive layer; forming a floating gate region; forming a second conductive layer on the third insulating layer; forming first sidewall spacers; forming control gates and a tunneling oxide; forming second sidewall spacers; and forming a drain region on the substrate.
摘要:
A semiconductor memory device. A trench capacitor disposed at a lower portion of a trench in a substrate, in which the trench capacitor comprises a filling electrode layer and a collar dielectric layer surrounding the filling electrode layer. The top of the collar dielectric layer is lower than top surface level of the filling electrode layer. A vertical transistor is disposed at the upper portion of the trench, comprising a doped region disposed in a portion of the trench adjacent to the trench. A buried conductive layer interposed between the vertical transistor and the trench capacitor, wherein the cross section of the buried conductive layer is H shaped. The trench capacitor and the doping region of vertical transistor are electrically connected through the H shaped buried conductive layer.
摘要:
Memory cells with vertical transistor and capacitor and fabrication methods thereof. The memory cell comprises a substrate with a trench. A capacitor is disposed at the bottom of the trench. A first conductive layer is electrically coupled to the capacitor. The first conductive layer is isolated the substrate by a collar dielectric layer. A trench top oxide (TTO) layer is disposed on the first conductive layer. A vertical transistor is disposed over the TTO layer. The vertical transistor comprises a gate dielectric layer disposed on the sidewalls of the upper portion of the trench, and a metal gate disposed in the upper portion of the trench.
摘要:
A multi-layer gate stack structure of a field-effect transistor device is fabricated by providing a gate electrode layer stack with a polysilicon layer, a transition metal interface layer, a nitride barrier layer and then a metal layer on a gate dielectric, wherein the transition metal is titanium, tantalum or cobalt. Patterning the gate electrode layer stack comprises a step of patterning the metal layer and the barrier layer with an etch stop on the surface of the interface layer. Exposed portions of the interface layer are removed and the remaining portions are pulled back from the sidewalls of the gate stack structure leaving divots extending along the sidewalls of the gate stack structure between the barrier layer and the polysilicon layer. A nitride liner encapsulating the metal layer, the barrier layer and the interface layer fills the divots left by the pulled-back interface layer. The nitride liner is opened before the polysilicon layer is patterned. As the requirement for an overetch into the polysilicon layer during the etch of the metal layer, the barrier layer and the interface layer is omitted, the height of the polysilicon layer can be reduced. The aspect ration of the gate stack structure is improved, the feasibility of pattern and fill processes enhanced and the range of an angle under which implants can be performed is extended.
摘要:
Memory cells with vertical transistor and capacitor and fabrication methods thereof. The memory cell comprises a substrate with a trench. A capacitor is disposed at the bottom of the trench. A first conductive layer is electrically coupled to the capacitor. The first conductive layer is isolated the substrate by a collar dielectric layer. A trench top oxide (TTO) layer is disposed on the first conductive layer. A vertical transistor is disposed over the TTO layer. The vertical transistor comprises a gate dielectric layer disposed on the sidewalls of the upper portion of the trench, and a metal gate disposed in the upper portion of the trench.
摘要:
A method for forming isolation layer in a vertical DRAM. A semiconductor substrate with a plurality of first trenches is provided, with a collar dielectric layer is formed on a sidewall of each, and each filled with a first conducting layer. A patterned mask layer is formed on the semiconductor substrate, and the semiconductor substrate is etched using the patterned mask layer as an etching mask to form a plurality of second trenches. The patterned mask layer is removed. Each second trench is filled with an insulating layer acting as an isolation. Each of first conducting layers is etched to form a plurality of grooves. A doped area acting as a buried strap is formed in the semiconductor substrate beside each groove. A trench top insulating layer is formed in the bottom surface of each trench. Each first trench is filled with a second conducting layer acting as a gate.
摘要:
A vertical split gate flash memory cell. The memory cell includes a substrate, a floating gate, a control gate, a tunnel layer, a first doping region, and a second doping region. The floating gate is disposed in the lower portion of the trench and insulated from the adjacent substrate by a floating gate oxide layer. The control gate is disposed over the floating gate and insulated from the adjacent substrate by a control gate oxide layer. The inter-gate dielectric layer is disposed between the floating gate and the control gate for insulation of the floating gate and the control gate. The first doping region is formed in the substrate adjacent to the control gate and the second doping region is formed in the substrate below the first doping region and adjacent to the floating gate to serve as source and drain regions with the first doping region.
摘要:
A semiconductor memory device. A trench capacitor disposed at a lower portion of a trench in a substrate, in which the trench capacitor comprises a filling electrode layer and a collar dielectric layer surrounding the filling electrode layer. The top of the collar dielectric layer is lower than top surface level of the filling electrode layer. A vertical transistor is disposed at the upper portion of the trench, comprising a doped region disposed in a portion of the trench adjacent to the trench. A buried conductive layer interposed between the vertical transistor and the trench capacitor, wherein the cross section of the buried conductive layer is H shaped. The trench capacitor and the doping region of vertical transistor are electrically connected through the H shaped buried conductive layer.