摘要:
A dual damascene process forms a two level metal interconnect structure by first providing a interlayer oxide over a device structure and covering the interlevel oxide layer with an etch stop layer. The etch stop layer is patterned to form openings corresponding to the pattern of the interconnects that are to be formed in the first level of the two level interconnect structure. After the etch stop layer is patterned, an intermetal oxide layer is provided over the etch stop layer. Because the etch stop layer is relatively thin, the topography formed on the surface of the intermetal oxide layer is relatively small. A photoresist mask is then provided over the intermetal oxide layer with openings in the mask exposing portions of the intermetal oxide layer in the pattern of the wiring lines to be provided in the second level of the interconnect structure. The intermetal oxide layer is etched and the etching process continues to form openings in the interlayer oxide where the interlayer oxide is exposed by the openings in the etch stop layer. Thus, in a single etching step, the openings for both the second level wiring lines and the first level interconnects are defined. Metal is then deposited over the structure and excess metal is removed by chemical mechanical polishing to define the two level interconnect structure.
摘要:
An improved dual damascene structure is provided for use in the wiring-line structures of multi-level interconnects in integrated circuit. In this dual damascene structure, low-K (low dielectric constant) dielectric materials are used to form both the di-electric layers and the etch-stop layers between the metal interconnects in the IC device. With this feature, the dual damascene structure can prevent high parasite capacitance to occur therein that would otherwise cause large RC delay to the signals being transmitted through the metal interconnects and thus degrade the performance of the IC device. With the dual damascene structure, such parasite capacitance can be reduced, thus assuring the performance of the IC device.
摘要:
A multilevel interconnect structure is formed in a manner that reduces the problems associated with the formation and subsequent filling of unlanded vias. A first level wiring line is provided on the surface of an interlayer dielectric. The upper surface and sidewalls of the first level wiring line are covered with an etch stop material that is different from the intermetal dielectric used to separate the first level of wiring line from upper levels of wiring lines. The intermetal dielectric layer is deposited over the first level wiring line and a via is etched through the intermetal dielectric to expose the etch stop material above the wiring line, with the via etch stopping on the etch stop material. Etch stop material is removed to expose a portion of the upper surface of the wiring line and a metal plug is formed within the via and then an upper level wiring line is formed in contact with the metal plug.
摘要:
A semiconductor fabrication method is provided for fabricating a shallow-trench isolation (STI) structure in an integrated circuit, which can prevent the occurrence of microscratches in the oxide plugs of the STI structure, thus further preventing the occurrence of a bridging effect and short-circuits between the circuit components that are intended to be electrically isolated by the STI structure. This method is characterized by the use of a laser annealing process to remove the microscratches that formed on the top surface of the oxide plugs during the chemical-mechanical polishing (CMP) process used to remove the upper part of the oxide layer to form the oxide plugs This method can therefore prevent the occurrence of a bridging effect and short-circuits due to the forming of the microscratches that would otherwise occur in the prior art.
摘要:
An improved dual damascene structure is provided for use in the wiring-line structures of multi-level interconnects in integrated circuit. In this dual damascene structure, low-K (low dielectric constant) dielectric materials are used to form both the di-electric layers and the etch-stop layers between the metal interconnects in the IC device. With this feature, the dual damascene structure can prevent high parasite capacitance to occur therein that would otherwise cause large RC delay to the signals being transmitted through the metal interconnects and thus degrade the performance of the IC device. With the dual damascene structure, such parasite capacitance can be reduced, thus assuring the performance of the IC device.
摘要:
An improved dual damascene structure is provided for use in the wiring-line structures of multi-level interconnects in integrated circuit. In this dual damascene structure, low-K (low dielectric constant) dielectric materials are used to form both the dielectric layers and the etch-stop layers between the metal interconnects in the IC device. With this feature, the dual damascene structure can prevent high parasite capacitance to occur therein that would otherwise cause large RC delay to the signals being transmitted through the metal interconnects and thus degrade the performance of the IC device. With the dual damascene structure, such parasite capacitance can be reduced, thus assuring the performance of the IC device.
摘要:
The capacitor of a DRAM cell is formed by depositing a layer of doped polysilicon, patterning the layer of doped polysilicon to define the extent of the capacitor's lower electrode and then depositing a first layer of hemispherical-grained silicon (HSG-Si) on the layer of doped polysilicon. Growth of the first layer of HSG-Si is interrupted and then a second layer of HSG-Si is grown. In one aspect, growth of the first layer of HSG-Si may be interrupted by either cooling the deposition substrate or stopping deposition for a period of time and then reinitiating deposition to provide a second layer of HSG-SI on the surface of the electrode. The interruption of the growth of the first layer, whether by cooling or by delay, is sufficient if the reinitiated growth initiates in a manner that is independent of the first process; i.e., the second layer of HSG-Si grows independently. In a different aspect of the invention, growth of the first layer may be interrupted by removing the electrode from the deposition system and performing an etch back operation. After the etch back operation, the electrode is reintroduced to the deposition system and a second layer of HSG-Si is grown on the etched surface. This textured silicon structure forms the lower electrode of the DRAM capacitor.
摘要:
The capacitor of a DRAM cell is formed by depositing a layer of doped polysilicon, patterning the layer of doped polysilicon to define the extent of the capacitor's lower electrode and then depositing a first layer of hemispherical-grained silicon (HSG-Si) on the layer of doped polysilicon. Growth of the first layer of HSG-Si is interrupted and then a second layer of HSG-Si is grown. In one aspect, growth of the first layer of HSG-Si may be interrupted by either cooling the deposition substrate or stopping deposition for a period of time and then reinitiating deposition to provide a second layer of HSG-Si on the surface of the electrode. The interruption of the growth of the first layer, whether by cooling or by delay, is sufficient if the reinitiated growth initiates in a manner that is independent of the first process; i.e., the second layer of HSG-Si grows independently. In a different aspect of the invention, growth of the first layer may be interrupted by removing the electrode from the deposition system and performing an etch back operation. After the etch back operation, the electrode is reintroduced to the deposition system and a second layer of HSG-Si is grown on the etched surface. This textured silicon structure forms the lower electrode of the DRAM capacitor.
摘要:
A high capacitance charge storage capacitor for a DRAM has a lower electrode in contact with one source/drain region of a transfer FET. The lower capacitor electrode includes a first layer of polysilicon deposited over part of the transfer FET and in contact with the source/drain region of the transfer FET. An oxide layer is deposited over the first polysilicon layer and then a sparse layer of hemispherical grained polysilicon is deposited on the surface of the oxide layer. The sparse layer of hemispherical grained polysilicon has grains on the order of approximately 100 nanometers across that are separated on the average by approximately 100 nanometers. The layer of oxide is etched using the sparse grains of hemispherical grained polysilicon as a mask, with the etch process stopping on the surface of the first layer of polysilicon. A second layer of polysilicon is deposited over the remaining grains of hemispherical grained polysilicon and over the column-shaped portions of the oxide layer left by the etching stop. A capacitor dielectric is formed over the second layer of polysilicon and then an upper capacitor electrode is provided.
摘要:
Hemispherical-grained silicon (HSG-Si) is grown on polysilicon by plasma deposition. A wider range of substrate deposition temperatures can be used in the plasma deposition of HSG-Si than can be maintained in the low pressure chemical vapor deposition (LPCVD) of HSG-Si. The plasma deposition of HSG-Si can be performed in an electron cyclotron resonance chemical vapor deposition (ECR-CVD) system at input power levels ranging from 100-1500 W, at total pressures between 5-60 mTorr, and at substrate temperatures ranging from 200.degree.-500.degree. C. A mixture of silane and hydrogen gases at a dilution ratio of silane within the silane and hydrogen gas mixture H.sub.2 /(SiH.sub.4 +H.sub.2) between about 70-99% may be used in the ECR-CVD system. The polysilicon surface is cleaned of native oxides prior to plasma deposition of HSG-Si.