Abstract:
A method for forming a semiconductor device is disclosed. A substrate including a gate dielectric layer and a gate electrode layer sequentially formed thereon is provided. An offset spacer is formed on sidewalls of the gate dielectric layer and the gate electrode layer. A carbon spacer is formed on a sidewall of the offset spacer, and the carbon spacer is then removed. The substrate is implanted to form a lightly doped region using the gate electrode layer and the offset spacer as a mask. The method may also include providing a substrate having a gate dielectric layer and a gate electrode layer sequentially formed thereon. A liner layer is formed on sidewalls of the gate electrode layer and on the substrate. A carbon spacer is formed on a portion of the liner layer adjacent the sidewall of the gate electrode layer. A main spacer is formed on a sidewall of the carbon spacer. The carbon spacer is removed to form an opening between the liner layer and the main spacer. The opening is sealed by a sealing layer to form an air gap.
Abstract:
Disclosed herein is a DRAM memory cell featuring a reduced size, increased retention time, and compatibility with standard logic manufacturing processes, making it well-suited for use as embedded DRAM. The memory cell disclosed herein includes a pass-gate transistor and a storage region. The transistor includes a gate and a drain. The storage region includes a trench, which is preferably a Shallow Trench Isolation (STI). A non-insulating structure, e.g., formed of polysilicon or metal, is located in the trench as serves as a capacitor node. The trench is partially defined by a doped sidewall that serves as a source for the transistor. The poly structure and the trench sidewall are separated by a dielectric layer. The write operation involves charge transport to the non-insulating structure by direct tunneling through the dielectric layer. The read operation is assisted by Gate Induced Drain Leakage (GIDL) current generated on the surface of the sidewall.
Abstract:
A semiconductor device including a contact etch stop layer and contact hole formation method for reduced underlying material loss and improved device performance, the method including providing a semiconductor substrate including an active region including a CMOS device, STI structures, and metal silicide regions; forming a fluorine doped amorphous carbon layer over the active region; forming a PMD layer on the fluorine doped amorphous carbon layer; dry etching contact holes in the PMD layer to expose the fluorine doped amorphous carbon layer; and, removing the fluorine doped amorphous carbon layer according to a dry stripping process.
Abstract:
A semiconductor device including a contact etch stop layer and contact hole formation method for reduced underlying material loss and improved device performance, the method including providing a semiconductor substrate including an active region including a CMOS device, STI structures, and metal silicide regions; forming a fluorine doped amorphous carbon layer over the active region; forming a PMD layer on the fluorine doped amorphous carbon layer; dry etching contact holes in the PMD layer to expose the fluorine doped amorphous carbon layer; and, removing the fluorine doped amorphous carbon layer according to a dry stripping process.
Abstract:
A method for forming a trench having upper rounded corners comprising the following steps. A substrate having an oxide layer formed thereover is provided. A hard mask layer is formed over the oxide layer. A patterned patterning layer is formed over the hard mask layer leaving one or more portions of the hard mask layer exposed. The hard mask layer is patterned using the patterned patterning layer as a mask to form a patterned hard mask layer having one or more openings exposing one or more portions of the oxide layer. The patterned patterning layer is removed. The oxide layer is patterned using the patterned hard mask layer as a mask using a first trench etching process to etch through the oxide layer at the one or more exposed portions of the oxide layer and into the substrate to form one or more shallow trenches within the substrate having upper rounded corners at the respective interfaces between substrate and patterned oxide layer. The substrate is further etched at the one or more shallow trenches using a second trench etching process to form one or more completed trenches having the upper rounded corners at the respective interfaces between substrate and patterned oxide layer.
Abstract:
A method to reduce the inverse narrow width effect in NMOS transistors is described. An oxide liner is deposited in a shallow trench that is formed to isolate active areas in a substrate. A photoresist plug is formed in the shallow trench and is recessed below the top of the substrate to expose the top portion of the oxide liner. An angled indium implant through the oxide liner into the substrate is then performed. The plug is removed and an insulator is deposited to fill the trenches. After planarization and wet etch steps, formation of a gate dielectric layer and a patterned gate layer, the NMOS transistor exhibits an improved Vt roll-off of 40 to 45 mVolts for both long and short channels. The improvement is achieved with no degradation in junction or isolation performance. The indium implant dose and angle may be varied to provide flexibility to the process.
Abstract:
Methods of forming MOSFET devices featuring LDD regions offset from the edges of conductive gate structures has been developed. A first embodiment of this invention features the definition of a tapered conductive gate structure with the foot of the tapered structure larger in width than the top of the structure. Formation of an LDD region is accomplished in regions of the semiconductor substrate not covered by the tapered conductive structure. A dry etch procedure is next used to remove the foot of the tapered conductive structure resulting in an LDD region being offset from the edges of a now straight walled conductive structure. A second embodiment of this invention entails the definition of a conductive gate structure featuring notches located at the bottom of the conductive gate structure, extending inwards. Formation of an LDD region is again accomplished in regions of the semiconductor substrate not underlying the non-notched portion of the conductive gate structure, resulting in the LDD region being offset from the notched edges of the conductive gate structure.
Abstract:
A method for forming a dual damascene with improved profiles including providing a semiconductor process wafer including a dielectric insulating layer and an overlying hardmask layer; forming an uppermost layer of amorphous carbon substantially conformally over the hardmask layer; forming a trench line opening through at least the thickness of the amorphous carbon layer; forming a dual damascene opening comprising forming the trench line opening overlying a via opening pattern through a thickness of the hardmask layer and partially through a thickness of the dielectric insulating layer; and, filling the dual damascene opening with metal.
Abstract:
A method for semiconductor device feature development using a bi-layer photoresist including providing a non-silicon containing photoresist layer over a substrate; providing a silicon containing photoresist over the non-silicon containing photoresist layer; exposing said silicon containing photoresist layer to an activating light source an exposure surface defined by an overlying pattern according to a photolithographic process; developing said silicon containing photoresist layer according to a photolithographic process to reveal a portion the non-silicon containing photoresist layer; and, dry developing said non-silicon containing photoresist layer in a plasma reactor by igniting a plasma from an ambient mixture including at least oxygen, carbon monoxide, and argon.
Abstract:
The present invention discloses a method and apparatus for controlling air flow in a liquid coating apparatus by providing an adjustable housing that consists of an upper compartment and a lower compartment such that the height of the cavity contained therein can be adjusted. Subsequently, the spacing between a substrate to be coated and the interior wall of the upper compartment can be suitably adjusted to allow a desirable quantity of air flowing therethrough. The redeposition of liquid coating particles thrown off the substrate surface during a spin coating process and then bouncing back from the interior wall of the upper compartment onto the substrate surface can be prevented. The contamination of the substrate surface can therefore be eliminated or reduced. The present invention adjusting means may further include a removable roof member which can be turned by thread means to adjust the spacing between the bottom surface of the roof member and the substrate resulting in an adjustable air flow rate through such spacing.