Abstract:
A method for forming a metal layer using an atomic layer deposition process. A sacrificial metal atomic layer is formed on a semiconductor substrate by reacting a precursor containing a metal with a reducing gas, and a metal atomic layer is formed of metal atoms separated from a metal halide gas on a semiconductor substrate by reacting the sacrificial metal atomic layer with a metal halide gas. Also, a silicon atomic layer may be additionally formed on the metal atomic layer using a silicon source gas, to thereby alternately stack metal atomic layers and silicon layers. Thus, a metal layer or a metal silicide layer having excellent step coverage can be formed on the semiconductor substrate.
Abstract:
Integrated circuit devices include a first dielectric layer, an electrically insulating layer on the first dielectric layer and an an aluminum oxide buffer layer formed by atomic layer deposition (ALD) and stabilized by heat treatment at a temperature of less than about 600.degree. C., between the first dielectric layer and the electrically insulating layer. The first dielectric layer may comprise a high dielectric material such as a ferroelectric or paraelectric material. The electrically insulating layer may also comprise a material selected from the group consisting of silicon dioxide, borophosphosilicate glass (BPSG) and phosphosilicate glass (PSG). To provide a preferred integrated circuit capacitor, a substrate may be provided and an interlayer dielectric layer may be provided on the substrate. Here, a metal layer may also be provided between the interlayer dielectric layer and the first dielectric layer. The metal layer may comprise a material selected from the group consisting of Pt, Ru, Ir, and Pd.
Abstract:
A method of forming an interconnection by using a landing pad is disclosed. In a semiconductor device having a memory cell portion and a peripheral circuit portion, a refractory metal is used for the bitline instead of the usual polycide, to concurrently form a contact on each active region of an N-type and a P-type, then a landing pad is formed on the peripheral circuit portion when a bitline is formed on the memory cell portion. In such a process, a substantial contact hole for the interconnection is formed on the landing pad so that an aspect ratio of the contact can be lowered. Accordingly, when forming a metal interconnection, the contact hole for the interconnection is easily filled by Al reflow so that the coverage-step of the metal being depositing in the contact hole for the interconnection is enhanced, the contact resistance is reduced. Further, the reliability of the semiconductor device is improved.
Abstract:
A wiring layer of a semiconductor device having a novel contact structure is disclosed. The semiconductor device includes a semiconductor substrate, an insulating layer having an opening (contact hole or via), a reactive spacer formed on the sidewall of the opening or a reactive layer formed on the sidewall and on the bottom surface of the opening and a first conductive layer formed on the insulating layer which completely fills the opening. Since the reactive spacer or layer is formed on the sidewall of the opening, when the first conductive layer material is deposited, large islands will form to become large grains of the sputtered Al film. Also, providing the reactive spacer or layer improves the reflow of the first conductive layer during a heat-treating step for filling the opening at a high temperature below a melting temperature. Thus, complete filling of the opening with sputtered Al can be ensured. All the contact holes, being less than 1 .mu.m in size and having an aspect ratio greater than 1.0, can be completely filled with Al, to thereby enhance the reliability of the wiring of a semiconductor device.
Abstract:
A wiring layer of a semiconductor device having a novel contact structure is disclosed. The semiconductor device includes a semiconductor substrate, an insulating layer having an opening (contact hole) and a first conductive layer formed on the insulating layer which completely fills the opening. The first conductive layer does not produce any Si precipitates in a subsequent heat-treating step for filling the opening with the first conductive layer material. The semiconductor device may further include a second conductive layer having a planarized surface on the first conductive layer. This improves subsequent photolithography. An anti-reflective layer may be formed on the second conductive layer for preventing an unwanted reflection during a photo lithography process. The semiconductor device preferably includes a diffusion barrier layer under the first conductive layer and on the semiconductor substrate, on the insulating layer, and on the inner surface of the opening which prevents a reaction between the first conductive layer and the semiconductor substrate or the insulating layer. A method for forming the wiring layer is also disclosed. Providing a semiconductor device with the wiring layer reduces the leakage current by preventing Al spiking. Since the first conductive layer undergoes a heat-treatment step at a temperature below the melting point, while flowing into the opening and completely filling it with the first conductive layer material, no void is formed in the opening. Good semiconductor device reliability is ensured in spite of the contact hole being less than 1 .mu.m in size and having an aspect ratio greater than 1.0.
Abstract:
A method for forming a metal layer including the steps of heat treating a semiconductor substrate for a predetermined time at an intermediate temperature between 200.degree. C. and 400.degree. C., then depositing the metal layer on the semiconductor substrate at a temperature below 200.degree. C., in a vacuum, then thermally treating the metal layer at a temperature between 0.6 Tm-1.0 Tm (where Tm is the melting point of the metal layer), without breaking the vacuum, thereby reflowing the grains of the metal layer, and then gradually cooling the metal layer. Alternatively, the intermediate heat-treatment step can be performed after the metal layer is thermally treated, in which case, the metal layer should thereafter be rapidly cooled.
Abstract:
The invention relates to a wiring structure for a semiconductor device and a method for manufacturing the same, which fills up a contact hole of below one half micron. An insulating layer is formed on a semiconductor substrate, and a contact hole is formed in the insulating layer. On the insulating layer, a first metal is deposited via a CVD method to form a CVD metal layer or a CVD metal plug filling up the contact hole. Then, the thus-obtained CVD metal layer or the CVD metal plug is heat-treated in a vacuum at a high temperature below the melting point of the first metal, thereby planarizing the surface of the CVD metal layer. A second metal is deposited via a sputtering method on the CVD metal layer or on the CVD metal plug to thereby form a sputtered metal layer. The contact hole is filled up with the first metal by the CVD method and then a reliable sputtered metal layer is deposited via a sputtering method. The wiring layer can be used for semiconductor devices of the next generation.
Abstract:
A semiconductor device and manufacturing method thereof having a diffusion barrier layer formed on a semiconductor wafer. The diffusion barrier layer has a surface region provided with a silylation layer which is formed on the diffusion barrier layer by a plasma process using silicon hydride or by a reactive sputtering method using SiH.sub.4. When a metal layer is formed on the silylation layer, the wettability between the diffusion barrier layer and the metal is enhanced and large grains are formed, thereby increasing the step coverage for the contact hole of the metal layer or for the via hole. Additionally, when heat treatment is performed after the metal layer is formed on the silylation layer, the reflow characteristic of the metal layer becomes good, to thereby facilitate the filling of the contact hole or the via hole. When the wiring layer is thus formed, metal wiring having good reliability can be obtained and a subsequent scintering process is rendered unnecessary.