摘要:
A new method is provided to create a gradated dopant concentration in the contact plug of DRAM devices whereby a high dopant concentration is present at the bottom of the plug and a low dopant concentration is present at the top of the plug. Two layers of dielectric are deposited; the upper layer serves as a layer to adjust the dopant concentration in the lower layer. This adjustment is done by Rapid Thermal anneal of both layers of dielectric. After the dopant concentration has been adjusted, the upper layer of dielectric is removed and the upper section of the contact node is formed using lightly doped poly. The high dopant concentration at the bottom of the contact plug results in low contact resistance between the plug and the underlying silicon substrate. A low dopant concentration at the top surface of the contact plug results in low oxidation of the surface of the plug.
摘要:
A new method based on measuring the weight of a wafer (on which the layer of HSG has been deposited) before (W1) and after (W2) the surface of the HSG layer is coated with a layer of either photoresist or SOG. The difference delta W=W2−W1 provides an indicator of the roughness or smoothness of the surface of the deposited layer of HSG. This new method can also be based on measuring the weight W of rejected or dropped PR or SOG after the surface of the HSG layer has been coated with a layer of either photoresist or SOG. The weight of the rejected or dropped PR or SOG also provides an indicator of the roughness or smoothness of the surface of the deposited layer of HSG.
摘要:
A method using a single masking step for making double-cylinder stacked capacitors for DRAMs which increases capacitance while eliminating erosion of an underlying oxide insulating layer when the masking step is misaligned is described. A planar silicon oxide (SiO2) first insulating layer is formed over device areas, and a first silicon nitride (Si3N4) etch-stop layer is deposited, and openings are etched for capacitor node contacts. A first polysilicon layer is deposited to a thickness sufficient to fill the openings and to form an essentially planar surface. A second insulating layer is deposited and patterned to form portions with vertical sidewalls over the node contacts. A conformal second Si3N4 layer is deposited and etched back to form spacers on the vertical sidewalls, and the first polysilicon layer is etched to the first Si3N4 layer. The second insulating layer is selectively removed using HF acid while the first polysilicon and first Si3N4 layers prevent etching of the underlying first SiO2 layer. A second polysilicon layer is deposited and etched back to form double-cylinder sidewalls for the capacitor bottom electrodes. The first and second Si3N4 layers are removed in hot phosphoric acid. The capacitors are completed by forming an interelectrode dielectric layer on the bottom electrodes, and depositing a third polysilicon layer for top electrodes.
摘要翻译:描述了一种使用单个掩模步骤来制造用于DRAM的双圆柱体堆叠电容器的方法,其在掩蔽步骤未对准时消除了下面的氧化物绝缘层的侵蚀,同时增加了电容。 在器件区域上形成平面氧化硅(SiO 2)第一绝缘层,并沉积第一氮化硅(Si 3 N 4)蚀刻停止层,并且蚀刻用于电容器节点接触的开口。 第一多晶硅层被沉积到足以填充开口并形成基本平坦的表面的厚度。 沉积和图案化第二绝缘层以在节点接触件上形成具有垂直侧壁的部分。 沉积保形第二Si 3 N 4层并回蚀刻以在垂直侧壁上形成间隔物,并且将第一多晶硅层蚀刻到第一Si 3 N 4层。 使用HF酸选择性地除去第二绝缘层,而第一多晶硅和第一Si 3 N 4层防止蚀刻下面的第一SiO 2层。 沉积第二多晶硅层并将其回蚀以形成用于电容器底部电极的双气缸侧壁。 在热磷酸中除去第一和第二Si 3 N 4层。 电容器通过在底部电极上形成电极间电介质层而形成,并且为顶部电极沉积第三多晶硅层。
摘要:
A method of forming a deep contact by forming a dielectric layer 20 over a semiconductor structure 10. A main point is that the hard mask 30 is removed after the plug 52 is formed. A hard mask layer 30 is formed over the dielectric layer 20. A contact photoresist layer 36 is formed over the hard mask layer 30. The hard mask layer 30 is etched through the contact photoresist opening 39 to form a contact hard mask opening 41 exposing the dielectric layer 20. The dielectric layer 20 is etched using a high density plasma etch process using the contact photoresist layer 36 and the hard mask layer 30 as an etch mask forming a contact hole 40 in the dielectric layer 20. The contact photoresist layer 36 is removed. A metal layer 50 is formed filling the contact hole 40 and covering over the hard mask layer 30. The metal layer 50 is etched back forming a plug 52 filling the contact hole 40. Now, the hard mask layer 30 is removed. The removal of the hard mask 30 after the metal layer 50 deposition: (a) prevents the contact hole 40 from being contaminated from photoresist and other contamination formed during the hard mask 30 removal steps; and (b) creates a plug 52 that does not have a recess.
摘要:
A new method of depositing PE-oxide or PE-TEOS. An HDP-oxide is provided over a pattern of polysilicon. An etch back is performed to the deposited HDP-oxide, a layer of plasma-enhanced SiN is deposited. This PE-SiN is etched back leaving SiN spacers on the sidewalls of the poly pattern, further leaving a deposition of HDP-oxide on the top surface of the poly pattern. The profile of the holes within the poly pattern in such that the final layer of PE-oxide or PE-TEOS is deposited without resulting in the formation of keyholes in this latter layer.
摘要:
A process for forming a DRAM, cylindrical shaped, stacked capacitor structure, located under a bit line structure, has been developed. The process features defining a polysilicon cell plate structure, during the same photolithotgraphic and anisotropic etching procedures, used to open a bit line contact hole. The bit line contact hole is formed by first opening a top portion of the bit line contact hole, using a photoresist shape as an etch mask, and after the formation of silicon nitride spacers, on the sides of the top portion of the bit line contact hole, the bottom portion of the bit line contact hole is opened, using silicon nitride as an etch mask.
摘要:
A process for forming crown shaped capacitor structures, for a DRAM device, has been developed. The process features the use of a disposable insulator layer, applied prior to photolithographic and dry etching procedures, used to define the capacitor upper plate structures. The disposable insulator layer alleviates the topography effects presented by crown shaped storage node structures, relaxing the complexity of the patterning of the capacitor upper plate structures.
摘要:
A method of forming a grooved fuse (plug fuse) in the same step that via plugs are formed in the guard ring area 14 and in product device areas. A key point of the invention is to form fuses from the via plug layer, not from the metal layers. Also, key guard rings are formed around the plug guise. The invention can include the following: a semiconductor structure is provided having a fuse area, a guard ring area surrounding the fuse area; and a device area. First and second conductive strips are formed. First and second insulating layers are formed over the first and second conductive strips. Plug contacts and fuse plugs are formed through the first and second insulating layers to the first and second conductive strips. A third insulating layer is formed over the second insulating layer. Metal lines are formed over the third insulating layer in the device area. A fuse via opening is formed in the third insulating layer. A plug fuse is formed in the fuse via opening. A fourth insulating layer is formed over the plug fuse and the third insulating layer. A fuse opening is formed at least partially though the fourth insulating layer over the fuse area.
摘要:
A method to form capacitance node contacts with improved isolation in a DRAM process is described. An isolation layer is formed on a semiconductor substrate. A first contact hole is formed and filled with a polysilicon plug and the top surface of the isolation layer and of the polysilicon plug are polished to a planar surface. A first interpoly isolation layer is deposited. A stopping layer is deposited. A capping layer is deposited. A first polysilicon layer is deposited. The first polysilicon layer is etched to form features. A second interpoly isolation layer is deposited. The second interpoly isolation layer is planarized. The second contact hole is etched through the second interpoly isolation layer and the capping layer. The exposed first polysilicon material is etched back to the vertical sides of the second contact hole. The stopping layer and the first interpoly isolation layer are etched through to the top surface of the polysilicon plug. A lining layer of silicon nitride is deposited and etched to remain only on the vertical interior surfaces of the second contact hole. A second polysilicon layer is deposited to fill the second contact hole. The second polysilicon layer and the second interpoly isolation layer are planarized. The fabrication of the integrated circuit device is completed.
摘要:
A robust dual damascene process is disclosed where the substructure in a substrate is protected from damage caused by multiple etchings required in a damascene process by filling a contact or via hole opening with a protective material prior to the forming of the conductive line opening of the damascene structure having an etch-stop layer separating a lower and an upper dielectric layer. In the first embodiment, the protective material is partially removed from the hole opening reaching the substructure prior to the forming of the upper conductive line opening by etching. In the second embodiment, the protective material in the hole is removed at the same time the upper conductive line opening is formed by etching. In a third embodiment, the disclosed process is applied without the need of an etch-stop layer for the dual damascene process of this invention.