摘要:
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.
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 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 polysilicon layer is subsequently deposited on the dielectric layer by using CVD. Next, photolithography and etching process are used to etch the doped polysilicon layer, and form a bottom electrode of DRAM cell capacitor with U shape in cross section view. The next step of the formation is the deposition of a dielectric film along the surface of the bottom electrode of DRAM cell capacitor. Typically, the dielectric film is preferably formed of high dielectric film such as tantalum oxide (Ta.sub.2 0.sub.5). A conductive layer is deposited over the dielectric film. The conductive layer is used as the top storage node and is formed of titanium nitride(TiN). The methods of forming the top storage node, including sputtered-TiN, collimated-sputtering TiN, and CVD/MOCVD-TiN deposition. The purposes of sputtered-TiN and collimated-sputtering TiN processes can improve the poor step coverage of deep well of bottom electrode of DRAM cell capacitor and protect the Ta.sub.2 0.sub.5 from C, Cl, F contamination during CVD/MOCVD-TiN deposition process.
摘要:
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.
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.