摘要:
A method for forming a DRAM MIM capacitor stack having low leakage current and low EOT involves the use of a first electrode that serves as a template for promoting the high k phase of a subsequently deposited first dielectric layer. The first high k dielectric layer comprises a doped material that can be crystallized after a subsequent annealing treatment. An amorphous, doped high k second dielectric material is form on the first dielectric layer. The dopant concentration and the thickness of the second dielectric layer are chosen such that the second dielectric layer remains amorphous after a subsequent annealing treatment. A second electrode layer compatible with the second dielectric layer is formed on the second dielectric layer.
摘要:
A method for fabricating a dynamic random access memory (DRAM) capacitor stack is disclosed wherein the stack includes a first electrode, a dielectric layer, and a second electrode. The first electrode is formed from a conductive binary metal compound and the conductive binary metal compound is annealed in a reducing atmosphere to promote the formation of a desired crystal structure. The binary metal compound may be a metal oxide. Annealing the metal oxide (i.e. molybdenum oxide) in a reducing atmosphere may result in the formation of a first electrode material (i.e. MoO2) with a rutile-phase crystal structure. This facilitates the formation of the rutile-phase crystal structure when TiO2 is used as the dielectric layer. The rutile-phase of TiO2 has a higher k value than the other possible crystal structures of TiO2 resulting in improved performance of the DRAM capacitor.
摘要翻译:公开了一种用于制造动态随机存取存储器(DRAM)电容器堆叠的方法,其中堆叠包括第一电极,电介质层和第二电极。 第一电极由导电二元金属化合物形成,导电二元金属化合物在还原气氛中退火以促进所需晶体结构的形成。 二元金属化合物可以是金属氧化物。 在还原气氛中退火金属氧化物(即氧化钼)可导致形成具有金红石相晶体结构的第一电极材料(即MoO 2)。 当使用TiO 2作为电介质层时,这有助于金红石相晶体结构的形成。 TiO 2的金红石相具有比其他可能的TiO 2晶体结构更高的k值,从而改善了DRAM电容器的性能。
摘要:
A method for forming a DRAM MIM capacitor stack having low leakage current and low EOT involves the use of an compound high k dielectric material. The dielectric material further comprises a dopant. One component of the compound high k dielectric material is present in a concentration between about 30 atomic % and about 80 atomic % and more preferably between about 40 atomic % and about 60 atomic %. In some embodiments, the compound high k dielectric material comprises an alloy of TiO2 and ZrO2 and further comprises a dopant of Al2O3. In some embodiments, the compound high k dielectric material comprises an admixture of TiO2 and HfO2 and further comprises a dopant of Al2O3.
摘要翻译:用于形成具有低漏电流和低EOT的DRAM MIM电容器堆叠的方法涉及使用复合高k电介质材料。 电介质材料还包括掺杂剂。 复合高k介电材料的一个组分以约30原子%至约80原子%,更优选约40原子%至约60原子%的浓度存在。 在一些实施方案中,化合物高k介电材料包含TiO 2和ZrO 2的合金,并且还包含Al 2 O 3的掺杂剂。 在一些实施方案中,化合物高k介电材料包含TiO 2和HfO 2的混合物,并且还包含Al 2 O 3的掺杂剂。
摘要:
A metal oxide first electrode material for a MIM DRAM capacitor is formed wherein the first and/or second electrode materials or structures contain layers having one or more dopants up to a total doping concentration that will not prevent the electrode materials from crystallizing during a subsequent anneal step. Advantageously, the electrode doped with one or more of the dopants has a work function greater than about 5.0 eV. Advantageously, the electrode doped with one or more of the dopants has a resistivity less than about 1000 μΩ cm. Advantageously, the electrode materials are conductive molybdenum oxide.
摘要:
A method for processing dielectric materials and electrodes to decrease leakage current is disclosed. The method includes a post dielectric anneal treatment in an oxidizing atmosphere to reduce the concentration of oxygen vacancies in the dielectric material. The method further includes a post metallization anneal treatment in an oxidizing atmosphere to reduce the concentration of interface states at the electrode/dielectric interface and to further reduce the concentration of oxygen vacancies in the dielectric material.
摘要:
A metal oxide bilayer second electrode for a MIM DRAM capacitor is formed wherein the layer of the electrode that is in contact with the dielectric layer (i.e. bottom layer) has a desired composition and crystal structure. An example is crystalline MoO2 if the dielectric layer is TiO2 in the rutile phase. The other component of the bilayer (i.e. top layer) is a sub-oxide of the same material as the bottom layer. The top layer serves to protect the bottom layer from oxidation during subsequent PMA or other DRAM fabrication steps by reacting with any oxygen species before they can reach the bottom layer of the bilayer second electrode.
摘要:
A method for reducing leakage current in DRAM capacitor stacks by introducing dielectric interface layers between the electrodes and the bulk dielectric material. The dielectric interface layers are typically amorphous dielectric materials with a k value between about 10 and about 30 and are less than about 1.5 nm in thickness. Advantageously, the thickness of each of the dielectric interface layers is less than 1.0 nm. In some cases, only a single dielectric interface layer is used between the bulk dielectric material and the second electrode.
摘要:
A method for forming a DRAM MIM capacitor stack having low leakage current involves the use of a first electrode that serves as a template for promoting the high k phase of a subsequently deposited dielectric layer. The high k dielectric layer comprises a doped material that can be crystallized after a subsequent annealing treatment. An amorphous blocking is formed on the dielectric layer. The thickness of the blocking layer is chosen such that the blocking layer remains amorphous after a subsequent annealing treatment. A second electrode layer compatible with the blocking layer is formed on the blocking layer.
摘要:
In some embodiments of the present invention, methods are developed wherein a gas flow of an electron donating compound (EDC) is introduced in sequence with a precursor pulse and alters the deposition of the precursor material. In some embodiments, the EDC pulse is introduced sequentially with the precursor pulse with a purge step used to remove the non-adsorbed EDC from the process chamber before the precursor is introduced. In some embodiments, the EDC pulse is introduced using a vapor draw technique or a bubbler technique. In some embodiments, the EDC pulse is introduced in the same gas distribution manifold as the precursor pulse. In some embodiments, the EDC pulse is introduced in a separate gas distribution manifold from the precursor pulse.
摘要:
A method for forming a capacitor stack is described. In some embodiments of the present invention, a first dielectric material is formed above a first electrode material. The first electrode material is rigid and has good mechanical strength and serves as a robust frame for the capacitor stack. The first dielectric material is sufficiently thin ( 3 nm) or lightly doped or non-doped so that it crystallizes after subsequent anneal treatments. A second electrode material is formed adjacent to the second dielectric material. The second electrode material has a high work function and a crystal structure that serves to promote the formation of the high k-value crystal structure of the second dielectric material.