Abstract:
A common problem associated with damascene structures made of copper inlaid in FSG (fluorinated silicate glass) is the formation of defects near the top surface of the structure. The present invention avoids this problem by laying down a layer of USG (undoped silicate glass) over the surface of the FSG layer prior to patterning and etching the latter to form the via hole and (for a dual damascene structure) the trench. After over-filling with copper, the structure is planarized using CMP. The USG layer acts both to prevent any fluorine from the FSG layer from reaching the copper and as an end-point detector during CMP. In this way defects that result from copper-fluorine interaction do not form and precise planarization is achieved.
Abstract:
A semiconductor device having a nonconductive cap layer comprising a first metal element. The nonconductive cap layer comprises a first metal nitride, a first metal oxide, or a first metal oxynitride over conductive lines and an insulating material between the conductive lines. An interface region may be formed over the top surface of the conductive lines, the interface region including the metal element of the cap layer. The cap layer prevents the conductive material in the conductive lines from migrating or diffusing into adjacent subsequently formed insulating material layers. The cap layer may also function as an etch stop layer.
Abstract:
A method of forming a silicided gate of a field effect transistor on a substrate having active regions is provided. The method includes the following steps: (a) forming a silicide in at least a first portion of a gate; (b) after step (a), depositing a metal over the active regions and said gate; and (c) annealing to cause the metal to react to form silicide in the active regions, wherein the thickness of said gate silicide is greater than the thickness of said silicide in said active regions.
Abstract:
A novel process for re-distributing a barrier layer deposited on a single damascene, dual damascene or other contact opening structure. The process includes providing a substrate having a contact opening structure and a metal barrier layer deposited in the contact opening structure, re-sputtering the barrier layer by bombarding the barrier layer with argon ions and metal ions, and re-sputtering the barrier layer by bombarding the barrier layer with argon ions.
Abstract:
A method of manufacturing a semiconductor device is provided comprising the steps of: (a) forming a semiconductor element on a substrate, the semiconductor element having at least one nickel silicide contact region, a first etch stop layer formed over the element and an insulating layer formed over the first etch stop layer; (b) forming an opening through the insulating layer over the contact region at least to the first etch stop layer; (c) removing a portion of the first etch stop layer contacting a selected contact region using a process that does not substantially oxidize with the contact region, to form a contact opening to the contact region; and (d) filling the contact opening with conductive material to form a contact.
Abstract:
A process for reducing the thermal budget and enhancing stability in the thermal budget of a metal salicide process used in the formation of metal salicides on substrates, thus eliminating or reducing salicide spiking and junction leakage in microelectronic devices fabricated on the substrates. According to a typical embodiment, a substrate is cooled to a sub-processing temperature which is lower than the metal deposition processing temperature and the salicide-forming metal is deposited onto the reduced-temperature substrate.
Abstract:
A method for forming a copper damascene feature including providing a semiconductor process wafer including at least one via opening formed to extend through a thickness of at least one dielectric insulating layer and an overlying trench line opening encompassing the at least one via opening to form a dual damascene opening; etching through an etch stop layer at the at least one via opening bottom portion to expose an underlying copper area; carrying out a sub-atmospheric DEGAS process with simultaneous heating of the process wafer in a hydrogen containing ambient; carrying out an in-situ sputter-clean process; and, forming a barrier layer in-situ to line the dual damascene opening.
Abstract:
An ALD method is described for depositing a composite layer comprised of three to five elements including one or two metals, Si, B and N. A metal containing gas is injected into a process chamber and purged followed by a N source gas and a purge and/or a Si or B source gas and a purge to complete a cycle and form a monolayer. A predetermined number of monolayers each having two or three elements is deposited to provide a composite film with good step coverage and a well controlled composition. The resulting layer is especially useful as a diffusion barrier layer for copper. Alternatively, a three component layer comprised of Hf, Zr, and O may be deposited and serves as a gate dielectric layer in a MOSFET device. The invention is also a thin film comprised of a plurality of monolayers each having two or three elements.
Abstract:
A method for integrating low-K materials in semiconductor fabrication. The process begins by providing a semiconductor structure having a dielectric layer thereover, wherein the dielectric layer comprising an organic low-K material. The dielectric layer is patterned to form pillar openings. A pillar layer is deposited over the semiconductor structure; thereby filling the pillar openings with the pillar layer. The pillar layer is planarized to form pillars embedded in said dielectric layer. The pillar layer comprises a material having good thermal stability, good structural strength, and good bondability of spin coating back-end materials, improving the manufacturability of organic, low-K dielectrics in semiconductor fabrication. In one embodiment, the pillars are formed prior to forming dual damascene interlayer contacts. In another embodiment, pillars are formed simultaneously with interlayer contacts.
Abstract:
A general process is described for filling a hole or trench at the surface of an integrated circuit without trapping voids within the filler material. A particular application is the filling of a trench with copper in order to form damascene wiring. First, a seed layer is deposited in the hole or trench by means of PVD. This is then followed by a sputter etching step which removes any overhang of this seed layer at the mouth of the trench or hole. A number of process variations are described including double etch/deposit steps, varying pressure and voltage in the same chamber to allow sputter etching and deposition to take place without breaking vacuum, and reduction of contact resistance between wiring levels by reducing via depth.