摘要:
The present invention relates to a method for preparing cerium oxide which enables preparation of cerium oxide showing improved polishing performance, cerium oxide prepared therefrom, and CMP slurry comprising the same.The method for preparing cerium oxide comprises the step of contacting cerium oxide with primary alcohol to increase specific surface area of the cerium oxide 10% or more.
摘要:
In a method for preparing cerium carbonate powder by mixing a cerium precursor solution with a urea solution and carrying out a precipitation reaction, wherein the cerium carbonate powder has a hexagonal crystal structure, by using at least one type of organic solvent as a solvent for either or both the cerium precursor solution and the urea solution, and adjusting temperature of the precipitation reaction within a range of 120° C. to 300° C. Also, the method can yield cerium carbonate powder, cerium oxide powder from the cerium carbonate powder, and CMP slurry including the cerium oxide powder as an abrasive. In the method, urea as a precipitant can improve the uniformity of a reaction, and thus it is possible to easily and inexpensively obtain cerium carbonate powder with a hexagonal crystal structure without the danger by high-temperature high-pressure and the need for an expensive system in hydrothermal synthesis.
摘要:
Disclosed is a method for directly preparing cerium oxide powder in a solution phase by a) mixing a cerium precursor solution with a precipitant solution to cause a reaction; and b) performing oxidation treatment of the reacted solution, wherein at least one kind of pure organic solvent containing no water is used as a solvent for the cerium precursor solution as well as the precipitant solution to thereby prepare the cerium oxide powder, the particle size of which is adjusted to 50 nm to 3 μm. Cerium oxide powder obtained from the method and CMP slurry comprising the cerium oxide powder as a polishing agent are also disclosed. The method makes it possible to prepare cerium oxide powder with an average particle size of 50 nm or greater and high crystallinity, which is difficult to prepare by the conventional wet precipitation process, by using an organic solvent as a solvent in a wet precipitation process, and the so-prepared cerium oxide powder can be used as a polishing agent for CMP slurry even without being subjected to separate heat treatment.
摘要:
In a method for preparing cerium carbonate powder by mixing a cerium precursor solution with a carbonate precursor solution and carrying out a precipitation reaction, wherein cerium carbonate is controlled to have an orthorhombic crystal structure, a hexagonal crystal structure or an orthorhombic/hexagonal mixed crystal structure, by using at least one type of organic solvent comprising at least two hydroxyl groups (OH) in molecular formula as a solvent for either or both the cerium precursor solution and the carbonate precursor solution, and varying a number of carbons or hydroxyl groups (OH) included in the molecular formula of the organic solvent. The method can easily and inexpensively obtain cerium carbonate powder with a desired crystal structure without the danger by high-temperature high-pressure and the need for an expensive system in hydrothermal synthesis.
摘要:
A wearable system and a method for transferring and controlling information/service based on biologically generated information from a user are provided. In the method, an intuitive bio signal generated by a user is sensed and a device pointed by the sensed bio signal is selected. Then, bio signal information is created using the sensed bio signal and the generated bio signal information is transmitted to the selected device. After transmitting, the information/service is transferred to the selected device after confirming that the selected device that receives the bio signal information is activated.
摘要:
Provided are a highly integrated semiconductor device with a silicide layer, which can secure a contact margin, and a method of manufacturing the highly integrated semiconductor device. The highly integrated semiconductor device includes a gate electrode formed on a semiconductor substrate. A source region and a drain region are formed in predetermined upper portions of the semiconductor substrate on two sides of the gate electrode such that each of the source region and the drain region includes a lightly doped drain (LDD) region and a heavily doped region. A silicide layer is formed on the gate electrode, the source region, and the drain region. The silicide layer has a sufficient thickness to function as an ohmic contact and is formed on the LDD region and the heavily doped region of each of the source region and the drain region.
摘要:
There is provided a method of fabricating a MOS transistor having a fully silicided gate, including forming a gate pattern and gate spacers on a semiconductor substrate, the gate pattern including a lower gate pattern, an insulating layer pattern, and an upper gate pattern, which are sequentially stacked. Source/drain regions are formed by implanting impurity ions into an active region using the gate pattern and the gate spacers as ion implantation masks. Then, a protecting layer is formed on the semiconductor substrate having the gate pattern, and the protecting layer is planarized until the upper gate pattern is exposed. Then, by removing the exposed upper gate pattern and the insulating layer pattern, the lower gate pattern is exposed. Then, the protecting layer is selectively removed, thereby exposing the source/drain regions. The exposed lower gate pattern is fully converted to a gate silicide layer, and a silicide layer is concurrently formed on the surfaces of the source/drain regions.
摘要:
Provided are a highly integrated semiconductor device with a silicide layer, which can secure a contact margin, and a method of manufacturing the highly integrated semiconductor device. The highly integrated semiconductor device includes a gate electrode formed on a semiconductor substrate. A source region and a drain region are formed in predetermined upper portions of the semiconductor substrate on two sides of the gate electrode such that each of the source region and the drain region includes a lightly doped drain (LDD) region and a heavily doped region. A suicide layer is formed on the gate electrode, the source region, and the drain region. The silicide layer has a sufficient thickness to function as an ohmic contact and is formed on the LDD region and the heavily doped region of each of the source region and the drain region.
摘要:
There is provided a method of fabricating a MOS transistor having a fully silicided gate, including forming a gate pattern and gate spacers on a semiconductor substrate, the gate pattern including a lower gate pattern, an insulating layer pattern, and an upper gate pattern, which are sequentially stacked. Source/drain regions are formed by implanting impurity ions into an active region using the gate pattern and the gate spacers as ion implantation masks. Then, a protecting layer is formed on the semiconductor substrate having the gate pattern, and the protecting layer is planarized until the upper gate pattern is exposed. Then, by removing the exposed upper gate pattern and the insulating layer pattern, the lower gate pattern is exposed. Then, the protecting layer is selectively removed, thereby exposing the source/drain regions. The exposed lower gate pattern is fully converted to a gate silicide layer, and a silicide layer is concurrently formed on the surfaces of the source/drain regions.
摘要:
Disclosed is cerium oxide powder for a CMP abrasive, which can improve polishing selectivity of a silicon oxide layer to a silicon nitride layer and/or within-wafer non-uniformity (WIWNU) during chemical mechanical polishing in a semiconductor fabricating process. More particularly, the cerium oxide powder is obtained by using cerium carbonate having a hexagonal crystal structure as a precursor. Also, CMP slurry comprising the cerium oxide powder as an abrasive, and a shallow trench isolation method for a semiconductor device using the CMP slurry as polishing slurry are disclosed.