摘要:
A method for manufacturing the lower electrode of a DRAM capacitor. The method includes depositing polysilicon instead of amorphous silicon to form the lower electrode. Because polysilicon has a higher depositing temperature, it has a higher depositing rate capable of shortening depositing time. After forming the polysilicon lower electrode, the upper portion of the polysilicon layer is transformed into an amorphous layer by bombarding the polysilicon layer with ions to damage its internal structure. Eventually, hemispherical grain silicon is able to grow over the lower electrode, thereby increasing its surface area.
摘要:
A method of fabricating a DRAM capacitor uses tungsten nitride in the process of forming a capacitor. The structure of the capacitor is simple and the process is easily executed. Furthermore, the invention provides a method of forming tungsten nitride, comprising a step of implanting nitrogen into a tungsten silicide layer and a step of executing a rapid thermal process under ammonia gas to form a tungsten nitride layer on the surface of the tungsten silicide layer. The method of fabricating a DRAM capacitor comprises forming the tungsten silicide layer after forming a part smaller than a bottom electrode of the capacitor from doped polysilicon and forming tungsten nitride on the surface of the tungsten nitride layer.
摘要:
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.
摘要:
A method of fabricating a dielectric layer for a dynamic random access memory capacitor is described in which a tantalum pentoxide layer is deposited on the polysilicon storage electrode, followed by a two-step treatment on the tantalum pentoxide layer. The first treatment step includes a remote oxygen plasma or an ultraviolet-ozone treatment, followed by a spike annealing second treatment step.
摘要:
A semiconductor fabrication method is provided for the fabrication of a dielectric structure for a storage capacitor in dynamic random-access memory (DRAM). In particular, the resultant dielectric structure can be fabricated thinner and more structurally-undefective than the prior art. By the method, a first nitridation process is performed to form a dielectric layer over a bottom electrode. Next, a layer of silicon nitride is formed over the dielectric layer. This silicon nitride layer would be typically formed with an undesired rugged surface with many punctures. To eliminate this structural defect, a second nitridation process is performed on the silicon nitride layer. The resultant silicon nitride layer and the dielectric layer in combination constitute an ON structure serving as the intended dielectric structure. Alternatively, an oxide layer can be further formed over the silicon nitride layer to constitute an ONO structure serving as the intended dielectric structure. The second nitridation process can be carried out either through a rapid thermal treatment process with the use of nitrogen, ammonia, or a mixture of nitrogen and ammonia; or alternatively through a nitrogen plasma treatment process.
摘要:
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.
摘要:
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.
摘要:
A method for forming a high capacitance charge storage structure that can be applied to a substrate wafer having MOS transistor already formed thereon. The method is to form an insulating layer above the substrate wafer. Next, a contact window exposing a source/drain region is formed in the insulating layer. Then, a tungsten suicide layer, which functions as a lower electrode for the charge storage structure, is formed over the substrate. Thereafter, a tungsten nitride layer is formed over the tungsten silicide layer, and then a dielectric layer is formed over the tungsten nitride layer. The dielectric layer is preferably a tantalum oxide layer. Finally, a titanium nitride layer, which functions as an upper electrode for the charge storage structure, is formed over the tantalum oxide layer.
摘要:
A method for forming shallow trench isolation is disclosed. The method includes forming a trench in a semiconductor substrate, and then blanket depositing a silicon oxide layer over the semiconductor substrate by a plasma process, thereby substantially refilling the trench. Thereafter, a photoresist layer is formed on the plasma deposited silicon oxide layer, followed by etching back a portion of the photoresist layer. The plasma deposited silicon oxide layer is then isotropically etched, and the photoresist layer is then finally removed.
摘要:
A method for fabricating a gate. A gate oxide layer is formed on a substrate. A first doped polysilicon layer is formed on the gate oxide layer. A second doped polysilicon layer on the first doped polysilicon layer. A third doped polysilicon layer over the second polysilicon layer. The second doped polysilicon layer has a grain size larger than a grain size of both the first doped polysilicon layer and the third dope polysilicon layer.