The present invention makes clear and defines a congruent composition of a langasite-based oxide, and establishes a method of manufacturing a crystal by any desired composition of AE.sub.3ME.sub.1+a(Ga.sub.1-xAl.sub.x).sub.3+bSi.sub.2+cO.sub.14 (AE is an alkaline-earth metal, ME is Nb or Ta, 0x1, 0.5<a0 or 0<a<0.5, 0.5<b0 or 0<b0.5, and 0.5<c0 or 0<c<0.5, excluding a=b=c=0). This makes it possible to suppress the formation of an impurity, and improve the yield and crystal manufacturing rate. The raw material is a raw material mixture prepared by mixing an alkaline-earth metal or its carbonate or oxide, Nb or Ta or its oxide, Ga or its oxide, Al or its oxide, and Si or its oxide.

A crystal pattern forming method includes: an electromagnetic wave absorbing layer forming process for forming an electromagnetic wave absorbing layer on one of surfaces of a substrate; an amorphous film forming process for forming an amorphous film on the electromagnetic wave absorbing layer; a mask forming process for forming an electromagnetic wave blocking mask for blocking an electromagnetic wave on the other one of the surfaces of the substrate; and a crystallizing process for causing the substrate to be irradiated with the electromagnetic wave from the other one of the surfaces of the substrate through the electromagnetic wave blocking mask to crystallize a given region in the amorphous film. In the mask forming process, a recessed structure is formed on the other one of the surfaces of the substrate, by selectively removing the other one of the surfaces of the substrate to form a recessed portion.

A subtractive forming method that includes providing a material stack including a samarium and selenium containing layer and an aluminum containing layer in direct contact with the samarium and selenium containing layer. The samarium component of the samarium and selenium containing layer of the exposed portion of the material stack is etched with an etch chemistry comprising citric acid and hydrogen peroxide that is selective to the aluminum containing layer. The hydrogen peroxide reacts with the aluminum containing layer to provide an oxide etch protectant surface on the aluminum containing layer, and the citric acid etches samarium selectively to the oxide etch protectant surface. Thereafter, a remaining selenium component of is removed by elevating a temperature of the selenium component.

A communication device for receiving an interrogation signal at a first carrier frequency and for transmitting a response signal at a second carrier frequency is disclosed. The interrogation signal comprises the first carrier frequency modulated at the second carrier frequency. The communication device includes a sensor coupled to a demodulator. The sensor receives a low frequency input used to further modulate the interrogation signal. The demodulator demodulates the low frequency input from the first carrier frequency to thereby generate the response signal comprising the second carrier frequency and the low frequency input. The demodulator preferably includes a pyroelectric demodulator, a piezoelectric demodulator, or a detector diode. The demodulator preferably has a frequency response less than the first carrier frequency but greater than the second carrier frequency.

A method of forming a monolithic integrated PMUT and CMOS with a coplanar elastic, sealing, and passivation layer in a single step without bonding and the resulting device are provided. Embodiments include providing a CMOS wafer with a metal layer; forming a dielectric over the CMOS; forming a sacrificial structure in a portion of the dielectric; forming a bottom electrode; forming a piezoelectric layer over the CMOS; forming a top electrode over portions of the bottom electrode and piezoelectric layer; forming a via through the top electrode down to the bottom electrode and a second via down to the metal layer through the top electrode; forming a second metal layer over and along sidewalls of the first and second via; removing the sacrificial structure, an open cavity formed; and forming a dielectric layer over a portion of the CMOS, the open cavity sealed and an elastic layer and passivation formed.

A method of forming a monolithic integrated PMUT and CMOS with a coplanar elastic, sealing, and passivation layer in a single step without bonding and the resulting device are provided. Embodiments include providing a CMOS wafer with a metal layer; forming a dielectric over the CMOS; forming a sacrificial structure in a portion of the dielectric; forming a bottom electrode; forming a piezoelectric layer over the CMOS; forming a top electrode over portions of the bottom electrode and piezoelectric layer; forming a via through the top electrode down to the bottom electrode and a second via down to the metal layer through the top electrode; forming a second metal layer over and along sidewalls of the first and second via; removing the sacrificial structure, an open cavity formed; and forming a dielectric layer over a portion of the CMOS, the open cavity sealed and an elastic layer and passivation formed.

A bonding layer 3 is formed over a piezoelectric material substrate, and the bonding layer 3 is made of or more material selected from the group consisting of silicon nitride, aluminum nitride, alumina, tantalum pentoxide, mullite, niobium pentoxide and titanium oxide. Neutralized beam A is irradiated onto a surface 4 of the bonding layer and a surface of a supporting body to activate the surface of the bonding layer and the surface of the supporting body. The surface of the bonding layer and the surface of the supporting body are bonded by direct bonding.

A transceiver device for receiving an interrogation signal at a first carrier frequency and for transmitting a response signal at a second carrier frequency is disclosed. The interrogation signal comprises the first carrier frequency modulated at the second carrier frequency. The communication device includes a sensor coupled to a demodulator. The sensor receives a low frequency input used to further modulate the interrogation signal. The demodulator demodulates the low frequency input from the first carrier frequency to thereby generate the response signal comprising the second carrier frequency and the low frequency input. The demodulator preferably includes a pyroelectric demodulator, a piezoelectric demodulator, or a detector diode. The demodulator preferably has a frequency response less than the first carrier frequency but greater than the second carrier frequency.

A method of manufacturing a monocrystalline layer comprises the following successive steps: providing a donor substrate comprising a piezoelectric material of composition ABO.sub.3, where A consists of at least one element from among Li, Na, K, H, Ca; and B consists of at least one element from among Nb, Ta, Sb, V; providing a receiver substrate, transferring a layer called the seed layer from the donor substrate on to the receiver substrate, such that the seed layer is at the bonding interface, followed by thinning of the donor substrate layer; and growing a monocrystalline layer of composition ABO.sub.3 on piezoelectric material ABO.sub.3 of the seed layer where A consists of a least one of the following elements Li, Na, K, H; B consists of a least one of the following elements Nb, Ta, Sb, V; and A is different from A or B is different from B.

A method of forming a film can include heating a CVD reactor chamber containing a substrate to a temperature range between about 750 degrees Centigrade and about 950 degrees Centigrade, providing a first precursor comprising Al to the CVD reactor chamber in the temperature range, providing a second precursor comprising Sc to the CVD reactor chamber in the temperature range, providing a third precursor comprising nitrogen to the CVD reactor chamber in the temperature range, and forming the film comprising ScAlN on the substrate.