Abstract: In order to obtain a SOI wafer having an excellent ability of gettering metal impurities, an efficient method of manufacturing a SOI wafer, and a highly reliable MEMS device using such a SOI wafer, provided is a SOI wafer including: a support wafer (1) and an active layer wafer (6) which are bonded together with an oxide film (3) therebetween, each of the support wafer (1) and the active layer wafer (6) being a silicon wafer; a cavity (1b) formed in a bonding surface of at least one of the silicon wafers; and a gettering material (2) formed on a surface on a side opposite to the bonding surface.

Abstract: In order to obtain a SOI wafer having an excellent ability of gettering metal impurities, an efficient method of manufacturing a SOI wafer, and a highly reliable MEMS device using such a SOI wafer, provided is a SOI wafer including: a support wafer (1) and an active layer wafer (6) which are bonded together with an oxide film (3) therebetween, each of the support wafer (1) and the active layer wafer (6) being a silicon wafer; a cavity (1b) formed in a bonding surface of at least one of the silicon wafers; and a gettering material (2) formed on a surface on a side opposite to the bonding surface.

Abstract: In order to obtain a SOI wafer having an excellent ability of gettering metal impurities, an efficient method of manufacturing a SOI wafer, and a highly reliable MEMS device using such a SOI wafer, provided is a SOI wafer including: a support wafer (1) and an active layer wafer (6) which are bonded together with an oxide film (3) therebetween, each of the support wafer (1) and the active layer wafer (6) being a silicon wafer; a cavity (1b) formed in a bonding surface of at least one of the silicon wafers; and a gettering material (2) formed on a surface on a side opposite to the bonding surface.

Abstract: In order to obtain a SOI wafer having an excellent ability of gettering metal impurities, an efficient method of manufacturing a SOI wafer, and a highly reliable MEMS device using such a SOI wafer, provided is a SOI wafer including: a support wafer (1) and an active layer wafer (6) which are bonded together with an oxide film (3) therebetween, each of the support wafer (1) and the active layer wafer (6) being a silicon wafer; a cavity (1b) formed in a bonding surface of at least one of the silicon wafers; and a gettering material (2) formed on a surface on a side opposite to the bonding surface.

Abstract: A diplexer provides a high degree of design freedom for satisfying the requirements of electric characteristics so as to realize desired characteristics and at the same time can be downsized and a multiplexer is realized by using such a diplexer. The diplexer includes a filter having a first pass band and a filter having a second pass band with a frequency band at least twice as high as the frequency band of the first pass band, the filter having the first pass band being a filter of the lumped constant type, the filter having the second pass band being a filter of the distributed constant type.

Abstract: It is possible to generate an additionally attenuation pole in a laminate type band pass filter without adding an attenuation circuit and improve the attenuation characteristics of the laminate type band pass filter by independently controlling the frequencies of the attenuation poles. A diplexer is realized by using at least such a filter.

Abstract: It is possible to generate an additionally attenuation pole in a laminate type band pass filter without adding an attenuation circuit and improve the attenuation characteristics of the laminate type band pass filter by independently controlling the frequencies of the attenuation poles. A diplexer is realized by using at least such a filter.

Abstract: A diplexer provides a high degree of design freedom for satisfying the requirements of electric characteristics so as to realize desired characteristics and at the same time can be downsized and a multiplexer is realized by using such a diplexer. The diplexer includes a filter having a first pass band and a filter having a second pass band with a frequency band at least twice as high as the frequency band of the first pass band, the filter having the first pass band being a filter of the lumped constant type, the filter having the second pass band being a filter of the distributed constant type.