Abstract: A location based service method and location based service system is provided. The location based service method includes: making requests for position determination of a client terminal according to a first position determination method and a second position determination method, in response to a location based service request; receiving a position determination result according to the first position determination method, and generating first location data including additional information which corresponds to the position determination result according to the first position determination method; providing the client terminal with the first location data; receiving a position determination result according to the second position determination method, and generating second location data, the second location data being refined first location data; and providing the client terminal with the second location data.

Abstract: A ferroelectric capacitor and method for making the same are disclosed. The ferroelectric capacitor may be constructed on a silicon substrate such as SiO2 or Si3N4. The ferroelectric capacitor includes a bottom electrode, a layer of ferroelectric material, and a top electrode. The bottom electrode is constructed from a layer of platinum which is bonded to the silicon substrate by a layer of metallic oxide. The metallic oxide does not diffuse into the platinum; hence, a thinner layer of platinum may be utilized for the electrode. This reduces the vertical height of the capacitor and other problems associated with diffusion of the layer used to bond, the bottom electrode to the substrate surface.

Abstract: An improved ferroelectric FET structure in which the ferroelectric layer is doped to reduce retention loss. A ferroelectric FET according to the present invention includes a semiconductor layer having first and second contacts thereon, the first and second contacts being separated from one another. The ferroelectric FET also includes a bottom electrode and a ferroelectric layer which is sandwiched between the semiconductor layer and the bottom electrode. The ferroelectric layer is constructed from a perovskite structure of the chemical composition ABO3 wherein the B site comprises first and second elements and a dopant element that has an oxidation state greater than +4 in sufficient concentration to impede shifts in the resistance measured between the first and second contacts with time. The ferroelectric FET structure preferably comprises Pb in the A-site. The first and second elements are preferably Zr and Ti, respectively.

Abstract: A ferroelectric memory cell for storing information. The information is stored in the remnant polarization of a ferroelectric dielectric layer by setting the direction of the remnant polarization. The ferroelectric memory cell is designed to store the information at a temperature less than a first temperature. The memory cell includes top and bottom contacts that sandwich the dielectric layer which includes a ferroelectric material having a Curie point greater than the first temperature and less than 400° C. The dielectric layer is encapsulated in an oxygen impermeable material such that the encapsulating layer prevents oxygen from entering or leaving the dielectric layer. One of the contacts typically includes a platinum electrode. The other contact may include a similar electrode or a semiconductor layer having electrodes spaced apart thereon.

Abstract: A ferroelectric memory cell for storing information and a method for fabricating the same. The information is stored in the remnant polarization of a ferroelectric dielectric layer by setting the direction of the remnant polarization. The ferroelectric memory cell is designed to store the information at a temperature less than a first temperature. During the fabrication process, the memory cell is subjected to an annealing operation in the presence of hydrogen at a second temperature and a packaging operation at a third temperature. The memory cell includes top and bottom contacts that sandwich the dielectric layer which includes a ferroelectric material having a Curie point greater than the first temperature and less than the second and third temperatures. The dielectric layer is encapsulated in an oxygen impermeable material such that the encapsulating layer prevents oxygen from entering or leaving the dielectric layer.

Abstract: A method for constructing a device having a bottom electrode in contact with a layer of a ferroelectric dielectric material. In the method of the present invention, a layer of a field ferroelectric material is deposited on a substrate and etched to form a trench in which the bottom electrode is constructed. The bottom electrode is then deposited and a layer of the ferroelectric dielectric material is deposited over the bottom electrode and at least a portion of the field ferroelectric material. The ferroelectric layers are deposited in a perovskite state. These layers are etched back to the substrate in those areas that are outside of the device.

Abstract: A ferroelectric memory cell for storing information. The information is stored in the remnant polarization of a ferroelectric dielectric layer by setting the direction of the remnant polarization. The ferroelectric memory cell is designed to store the information at a temperature less than a first temperature. The memory cell includes top and bottom contacts that sandwich the dielectric layer which includes a ferroelectric material having a Curie point greater than the first temperature and less than 400.degree. C. The dielectric layer is encapsulated in an oxygen impermeable material such that the encapsulating layer prevents oxygen from entering or leaving the dielectric layer. One of the contacts is typically includes a platinum electrode. The other contact may include a similar electrode or a semiconductor layer having electrodes spaced apart thereon.