摘要:
The present invention relates to a new sulfonated polyimides, more specifically to new methods for preparing the polyimides, and cation exchange membranes containing the polyimides. The sulfonated polyimides of the presented invention have excellent proton conductivity and low preparation cost. In particular, the sulfonated polyimides can be used as polymer electrolyte membrane in hydrogen or direct methanol fuel cell for electric vehicles and portable power sources operated with electric energy
摘要:
A proton exchange polymer membrane whose surface is treated by direct fluorination using a fluorine gas, a membrane-electrode assembly, and a fuel cell comprising the same are provided. The proton exchange polymer membrane of the present invention exhibits improved proton conductivity, high dimensional stability, and decreased methanol permeability through introducing hydrophobic fluorine having high electronegativity to the surface of the polymer membrane. Therefore, the proton exchange polymer membrane with excellent electrochemical properties of the present invention can be preferably utilized as polymer electrolyte membrane for fuel cell, generating electric energy from chemical energy of fuels.
摘要:
A proton exchange polymer membrane whose surface is treated by direct fluorination using a fluorine gas, a membrane-electrode assembly, and a fuel cell comprising the same are provided. The proton exchange polymer membrane of the present invention exhibits improved proton conductivity, high dimensional stability, and decreased methanol permeability through introducing hydrophobic fluorine having high electronegativity to the surface of the polymer membrane. Therefore, the proton exchange polymer membrane with excellent electrochemical properties of the present invention can be preferably utilized as polymer electrolyte membrane for fuel cell, generating electric energy from chemical energy of fuels.
摘要:
A memory device may include a plurality of semiconductor patterns on a substrate including a plurality of first impurity regions doped at a first impurity concentration, a plurality of second impurity regions at portions of the substrate contacting the plurality of semiconductor patterns and doped at a second impurity concentration, a plurality of channel patterns on the plurality of semiconductor patterns, a plurality of gate structures, a plurality of third impurity regions at portions of the substrate adjacent to end portions of the plurality of gate structures, and a plurality of fourth impurity regions at portions of the substrate between the second and third impurity regions and between adjacent second impurity regions. The plurality of fourth impurity regions may be doped at a third impurity concentration which may be lower than the first and second impurity concentrations.
摘要:
A nonvolatile memory device includes a string selection transistor, a plurality of memory cell transistors, and a ground selection transistor electrically connected in series to the string selection transistor and to the pluralities of memory cell transistors. First impurity layers are formed at boundaries of the channels and the source/drain regions of the memory cell transistors. The first impurity layers are doped with opposite conductivity type impurities relative to the source/drain regions of the memory cell transistors. Second impurity layers are formed at boundaries between a channel and a drain region of the string selection transistor and between a channel and a source region of the ground selection transistor. The second impurity layers are doped with the same conductivity type impurities as the first impurity layers and have a higher impurity concentration than the first impurity layers.
摘要:
A nonvolatile memory device includes a string selection gate and a ground selection gate on a semiconductor substrate, and a plurality of memory cell gates on the substrate between the string selection gate and the ground selection gate. First impurity regions extend into the substrate to a first depth between ones of the plurality of memory cell gates. Second impurity regions extend into the substrate to a second depth that is greater than the first depth between the string selection gate and a first one of the plurality of memory cell gates immediately adjacent thereto, and between the ground selection gate and a last one of the plurality of memory cell gates immediately adjacent thereto. Related fabrication methods are also discussed.
摘要:
A nonvolatile memory device includes a string selection gate and a ground selection gate on a semiconductor substrate, and a plurality of memory cell gates on the substrate between the string selection gate and the ground selection gate. First impurity regions extend into the substrate to a first depth between ones of the plurality of memory cell gates. Second impurity regions extend into the substrate to a second depth that is greater than the first depth between the string selection gate and a first one of the plurality of memory cell gates immediately adjacent thereto, and between the ground selection gate and a last one of the plurality of memory cell gates immediately adjacent thereto. Related fabrication methods are also discussed.
摘要:
A method of fabricating a semiconductor device includes forming a fin-shaped active region including opposing sidewalls and a surface therebetween protruding from a substrate, forming a gate structure on the surface of the active region, and performing an ion implantation process to form source/drain regions in the active region at opposite sides of the gate structure. The source/drain regions respectively include a first impurity region in the surface of the active region and second impurity regions in the opposing sidewalls of the active region. The first impurity region has a doping concentration that is greater than that of the second impurity regions. Related devices are also discussed.
摘要:
A non-volatile memory device includes a dielectric layer between a charge storage layer and a substrate. Free bonds of the dielectric layer can be reduced to reduce/prevent charges from leaking through the free bonds and/or from being trapped by the free bonds. As a result, data retention properties and/or durability of a non-volatile memory device may be enhanced.
摘要:
A non-volatile memory device includes an array of flash memory cells therein and a voltage generator. The voltage generator is configured to generate a program voltage (Vpgm), a pass voltage (Vpass), a blocking voltage (Vblock) and a decoupling voltage (Vdcp) during a flash memory programming operation. The blocking voltage is generated at a level that inhibits inadvertent programming of an unselected memory cell(s). This voltage level of the blocking voltage is set so that Vdcp