Abstract: The present invention proposes a method for forming a tungsten film with a good surface property and utilizes a chemical plasma treatment to round the tungsten surface and to improve the leakage issue of tungsten conductive film. A fabrication of a DRAM cell capacitor with tungsten bottom electrode is described for a preferred embodiment. Forming an inter-layer dielectric on a semiconductor substrate, a tungsten layer is formed thereon. A chemical plasma treatment is carried out to round the tungsten surface spires and result in a better surface properties. The tungsten layer is patterned to serve as the bottom electrode, and another dielectric layer is formed to cover the bottom electrode of tungsten. Finally, the top storage electrode is formed to finish the present process.

Abstract: A method of forming a DRAM capacitor. A hemispherical grain structure is formed on the surface of the bottom electrode of the capacitor. By employing an additional annealing under a dopant contained ambient, the dopant is diffused into the hemispherical grain structure and distributed at the surface area of the hemispherical grain region.

Abstract: An apparatus and method which, in a wireless communication system, improve the quality of inter-frequency hand-offs from an existing call connection frequency to a new frequency by minimizing oscillating inter-frequency hand-offs between the existing call connection frequency and the new frequency, and by minimizing redundant and unnecessary tuning and searching at the new frequency. The present invention accomplishes this improvement by adding specific threshold comparison values (or triggers) within existing messages and through more robust data reporting, from the mobile unit to the base station, when tuning and searching is performed. Particularly, two comparative triggers provided by the present invention avoid unnecessary tuning and searching in the new frequency, thus reducing voice degradation and the risk of dropped calls while pilot searching in the current frequency.

Abstract: A copper-palladium alloy damascene technology applied to the ultra large scale integration (ULSI) circuits fabrication is disclosed. First, a TaN barrier is deposited over an oxide layer or in terms of the inter metal dielectric (IMD) layer. Then a copper-palladium seed is deposited over the TaN barrier. Furthermore, a copper-palladium gap-fill electroplating layer is electroplated over the dielectric oxide layer. Second, a copper-palladium annealing process is carried out. Then the copper-palladium electroplating surface is planarized by means of a chemical mechanical polishing (CMP) process. Third, the CoWP cap is self-aligned to the planarized copper-palladium alloy surface. Finally, a second IMD layer is deposited over the first IMD layer. Furthermore, a contact hole in the second dielectric layer over said CoWP cap layer is formed, and then the CoWP cap of the first IMD layer is connected with the copper-palladium alloy bottom surface of the second IMD layer directly.

Abstract: A method of reducing the leakage current of a dielectric layer of a capacitor. A substrate having a dielectric layer formed thereon is disposed into a furnace. A first annealing step is performed for nucleation. A second annealing step is performed to control the number of the nuclei. A third annealing step is performed for grain growth.

Abstract: A method for fabricating a metal interconnect structure. A semiconductor substrate comprising a conductive layer therein is provided. A dielectric layer is formed on the semiconductor substrate. A part of the dielectric layer is removed to form a dual damascene opening and a trench therein, wherein the dual damascene opening exposes the conductive layer. The trench is larger than the dual damascene opening. A conformal barrier layer is formed on the dielectric layer. A conformal metal layer is formed on the barrier layer to fill the dual damascene opening and to partially fill the trench. The metal layer positioned in the trench has a thickness equal to the depth of the trench. A conformal cap layer is formed on the metal layer. A CMP process is performed to remove the cap layer, the metal layer and the barrier layer outside the trench and outside the dual damascene opening.

Abstract: Several processes for forming semiconductor gate structures having treated titanium silicide layers are disclosed. There are at least three methods been provided for the present invention and a summarized general procedure of all the methods comprises the following steps: The first step is to provide a silicon substrate having a gate oxide layer formed on top the silicon substrate, and forming a polysilicon layer over the gate oxide layer, followed by the formation of a TiN layer over the polysilicon layer. A treated titanium silicide layer is then formed on top of the TiN layer. Sequentially, an anti-reflection (SiON) film is deposited on top of the treated titanium silicide layer with a capping layer formed over the anti-reflection film. Finally, patterning and etching the above layers to expose a portion of the gate oxide layer and to form a gate electrode, where the final gate structure is rounded up by a rapid thermal process (RTP).

Abstract: Methods and apparatus for estimating mobile station location in a wireless communication system. At initiation of a call or a page response, a mobile station of the system sends an access request signal to a primary base station. The primary base station responds with an access acknowledgment which may be intentionally delayed such that the mobile station increases its transmit power level. The primary base station then transmits a channel assignment message to the mobile station. The mobile station responds by transmitting a location signal in the form of a known user-specific traffic preamble at the higher transmit power level. The primary base station intentionally delays sending an acknowledgment of the preamble, such that the mobile station transmits the preamble for a longer period of time than it would otherwise.

Abstract: A method for fabricating a capacitor in an integrated circuit, using tantalum oxide as the dielectric layer to obtain a higher capacitance. A barrier layer is formed between the polysilicon layer and the tantalum oxide layer to prevent the formation of a silicon oxide layer. Thus, that capacitance of the capacitor is not reduced by the additional thickness of the silicon oxide layer.

Abstract: A fabricating method of a capacitor includes two gates and a commonly used source/drain region formed on a substrate. Then, a process of sell align contact has been applied to make a pitted self align contact window (PSACW) to partly expose the commonly used source/drain region. Then an glue/barrier layer and a lower electrode of the capacitor are formed over the PSACW. Then a dielectric thin film with a material having high dielectric constant is formed over the lower electrode. Then, an upper electrode is formed over the dielectric thin film to complete a capacitor, which has a structure of metal insulator metal with a shape like the PSACW.

Abstract: A method for forming a barrier/glue layer above the polysilicon layer of a MOS transistor gate comprising the step of providing a semiconductor substrate, and then forming a gate oxide layer above the substrate. Next, a polysilicon layer is formed over the gate oxide layer. Thereafter, a titanium layer is deposited over the polysilicon layer first, and then a titanium nitride layer is deposited above the titanium layer. This titanium/titanium nitride bi-layer is capable of increasing the adhesive strength with a subsequently deposited tungsten silicide layer, and preventing the peeling of the tungsten silicide layer. Furthermore, the titanium nitride layer acts as a barrier for fluorine atoms preventing their diffusion to the gate oxide layer/polysilicon layer interface, and affecting the effective thickness of the gate oxide layer. In the subsequent step, a tungsten suicide layer is formed above the titanium nitride layer.

Abstract: The present invention increases the success rate of soft handoffs by enhancing the ability of a mobile-telephone to receive a handoff direction message that identifies the traffic channel being assigned to enable a candidate base station to communicate with the mobile-telephone. Specifically, the aforementioned ability of the mobile-telephone is enhanced by using the candidate base station to transmit the handoff direction message on a communication channel belonging to the candidate base station and being listened to by the mobile-telephone. In situations where signals transmitted from active set base stations have a low signal-to-noise ratio at the mobile-telephone, signals transmitted from the candidate base station may have a higher signal-to-noise ratio at the mobile-telephone.

Abstract: A method for forming a DRAM capacitor whose titanium nitride electrode is fabricated in a sequence of steps that results in a good step-coverage. Moreover, contamination of the titanium nitride layer and cross-diffusion between the titanium nitride layer and the dielectric film layer is reduced to a minimum. The method of forming the titanium nitride layer includes the steps of depositing a first titanium nitride layer over a dielectric film layer using a conventional physical vapor deposition process. Then, a second titanium nitride layer is deposited over the first titanium nitride layer using a collimated physical vapor deposition process.

Abstract: A method for manufacturing a via structure comprising the steps of providing a semiconductor substrate, and then forming conductive line and dielectric layer over the substrate. Next, a photolithographic and a first etching operation are conducted so that an opening in the dielectric layer exposing the conductive line surface is formed. The first etching operation uses several etchants including fluorobutane, which has the highest concentration. Since there is a re-entrance structure at the bottom of the opening, a second etching operation is performed. In the second etching operation, a portion of the conductive line is etched for a fixed time interval to control the degree of etching. Consequently, a slanting surface is formed at the bottom of the opening and the re-entrance structure is eliminated. With a planarized bottom, step coverage of subsequently deposited material is increased.

Abstract: A structure of a capacitor includes two gates and a commonly used source/drain region on a substrate. Then, a pitted self align contact window (PSACW) partly exposes the commonly used source/drain region. Then an glue/barrier layer and a lower electrode of the capacitor are over the PSACW. Then a dielectric thin film with a material having high dielectric constant is over the lower electrode. Then, an upper electrode is over the dielectric thin film to complete a capacitor, which has a structure of metal insulator metal with a shape like the PSACW.

Abstract: A method for increasing the success rate for soft handoffs, particularly under rapidly fluctuating fading conditions, using traffic channels of active set base stations. In one embodiment of the present invention, increased success rate for soft handoffs is achieved using a candidate base station, in addition to the active set base stations, to transmit a handoff command message to the mobile-telephone. Specifically, the handoff command message is transmitted by the active set base stations over the traffic channels assigned to mobile-telephone for communicating with the active set base stations, and by the candidate base station over the traffic channel assigned to the mobile-telephone for communicating with a primary base station. Additionally, a pilot signal may be transmitted by the candidate base station to enable the mobile-telephone to coherently demodulate the handoff direction message transmitted by the candidate base station.

Abstract: A method of fabricating a capacitor, comprising the steps of: providing a conductive layer over a semiconductor substrate having a transistor formed thereon to connect a source/drain region of the transistor; forming a hemispherical grained silicon layer over the conductive layer; using an implantation method to implant ions into the hemispherical grained silicon layer; performing a thermal treatment process to convert the ions into a barrier layer over the hemispherical grained silicon layer; performing a wet etching process to clean a surface of the barrier layer; forming a dielectric layer over the barrier layer and forming a top electrode over the dielectric layer.

Abstract: A method is described for manufacturing a multilevel metal interconnects. The method comprises the steps of providing a substrate and then forming a wire on the substrate. A dielectric layer is formed on the substrate and the wire and a protective layer is formed on the dielectric layer. An opening is formed by patterning the protective layer and the dielectric layer and a barrier layer is formed on the protective layer and in the opening. A copper layer is formed on the barrier layer and fills the opening. A portion of the copper layer and the barrier layer are removed by chemical-mechanical polishing.

Abstract: A method of forming a metal plug. A contact window is formed to penetrate through a dielectric layer on a substrate having a MOS formed thereon. A titanium glue layer is formed on the dielectric layer and the circumference of the contact window. A titanium barrier layer is formed on the titanium nitride layer. Using nitrogen plasma bombardment on the titanium nitride layer, the structure of the titanium nitride layer is transformed. The number of the nucleation seeds is increased, and the size of grains is reduced. A metal layer is formed on the titanium nitride layer and fills the contact window. A part of the metal layer is removed and a metal plug within the contact window is formed.

Abstract: A method for inhibiting replication of reverse transcriptase dependent virus in plant or animal cells, comprising the step of administering to said cells a compound that depletes the intracellular pool of deoxyribonucleoside phosphate in an amount effective to inhibit replication of said virus. Hydroxyurea is one such suitable compound. Also disclosed is a method for producing incomplete reverse-transcriptase dependent viral DNA, by administering a deoxyribonucleoside phosphate-depleting drug to cells infected with such a virus.