Abstract: The present invention provides a fluorine-containing ether compound represented by the following Formula. R1-[B]-[A]-CH2—R2—CH2-[C]-[D]-R3 (R2 is a perfluoropolyether chain; [A] is Formula (2-1); [B] is Formula (2-2); [C] is Formula (3-1); [D] is Formula (3-2); R3 is Formula (4); and R1 is a terminal group.

Abstract: The present invention provides a technique of enabling communication devices constituting a wireless network to register and update identification information easily, and thereby ensuring security of the communication devices and the wireless network and of detecting a communication device suspected of accessing a wireless network illegally and informing a user of the communication device. Communication terminal 20b detects and reports networked devices constituting wireless LAN 1, and if communication with the reported networked devices is permitted through an operation of operating unit 204, registers the MAC addresses of the networked devices in permission table 206a. Communication terminal 20b permits communication with a networked device constituting wireless LAN 1 whose MAC address has been registered in permission table 206a, and prohibits communication with a networked device constituting wireless LAN 1 whose MAC address has not been registered in permission table 206a.

Abstract: A communication device comprises storing means, communicating means, determining means and data transfer control means. The storing means stores access parameters, the access parameters indicative of an attempt by a computer virus to install on a communication device a backdoor for transfer and installation of the virus on the communication device. The determining determines on the basis of data received by the communicating means and on the basis of the access parameters, whether a backdoor installation attempt by a computer virus is in progress. The data transfer control means controls data transfer so as to disregard and not to transfer received data when it is determined on the basis of the data and the access parameters that a backdoor installation attempt is in progress.

Abstract: Disclosed is a semiconductor memory device (DRAM) which includes a plurality of island regions, at least one cell transistor disposed on each island region and cylindrical capacitor surrounding said each island region. By so composing, the capacity of the cell capacitor incorporated into a small space can be increased.Also disclosed is method of fabricating a semiconductor memory device which includes a step of forming a groove having a necessary depth in a semiconductor substrate, a step of depositing a membrane excelling in coverage on it, a step of etching by an etching method having a strong anisotropy in the vertical direction while leaving said deposit membrane on sidewall, and a step of etching deeper the exposed portion of the semiconductor surface in the groove and forming capacity element and isolation region by using this deep trench.

Abstract: A semiconductor memory device (DRAM) includes a plurality of island regions, at least one cell transistor disposed on each island region and a cylindrical capacitor surrounding each island region. With such a structure, the capacity of the cell capacitor incorporated into a small space can be increased. Furthermore, a method of fabricating a semiconductor memory device includes a step of forming a groove having a necessary depth in a semiconductor substrate, a step of depositing a membrane having excellent covering characteristics in the groove, a step of etching by using an etching method having a strong anisotropy in the vertical direction while leaving the deposited membrane on a sidewall, and a step of etching the exposed portion of the semiconductor surface deeper in the groove and forming a capacity element and isolation region by using this deep trench.