Piezoelectric resonating device

Claim 2

A piezoelectric resonating device, comprising in combination: a body of piezoelectric material of relatively high conductivity forming a substrate having at least one surface; active material diFfused into said one surface of said substrate to form at least one principal area of resonance of less conductivity than said body of material such that the resonant frequency of said principal area of resonance is determined by a surface area of said active material which is less than the surface area of said one surface of said substrate and by a thickness of said active material which is less than the thickness of said body of material forming said substrate; electrode means supported only on the surface of said active material; and means for coupling signal information including signals within the resonant frequency of said principal areas of resonance across said electrode and said substrate.

Claim 3

The piezoelectric resonating device of claim 1 wherein said body is formed of zinc oxide and said active material is lithium.

Claim 4

The piezoelectric resonating device of claim 1 wherein the thickness of said body of material is a multiple of half wavelengths of the resonant frequency of said principal area of resonance.

Claim 5

The piezoelectric resonating device of claim 1 wherein said body of material has a first portion of a predetermined thickness in which one of said principal areas of resonance is formed and the second portion of a different thickness in which another of said principal areas of resonance is formed.

Claim 6

The piezoelectric resonating device of claim 1 wherein said body of material is tapered uniformly from one end to the other decreasing in thickness to provide principal areas of resonance which have greater frequency response than do principal areas of resonance in the immediately adjacent thicker portion of the tapered body.

Claim 7

The piezoelectric resonating device of claim 1 wherein a pair of principal areas of resonance are diffused into said substrate spaced from one another a first predetermined distance, and further including input electrode means in contact with and only supported on the surface of one of the principal areas of resonance and output electrode means in contact with and only supported on the surface of the other principal area of resonance, said electrode means being spaced from one another a second predetermined distance, the space between said electrode means over said second predetermined distance forming a capacitive coupling between said pair of principal areas of resonance; and means for coupling said substrate with a reference potential.

Claim 8

A piezoelectric resonating device comprising in combination: a body of piezoelectric material forming a substrate at one surface thereof; activating material in contact with said substrate at at least two spaced locations to form at least one pair of principal areas of resonance; input electrode means in contact with one of said principal areas of resonance and output electrode means in contact with the other of said principal areas of resonance; and at least a portion of a first composite thickness of said body of piezoelectric material, said activating material and one of said input and output electrode means being an even multiple of half-wavelengths of a predetermined frequency and at least a portion of a second composite thickness of said body, said activating material and the other of said input and output electrode means being an odd multiple of half-wavelengths of substantially said same predetermined frequency.

Claim 9

A piezoelectric resonating device comprising in combination: a body of piezoelectric material forming a substrate at one surface thereof; activating material in contact with said substrate at at least two spaced locations to form at least one pair of principal areas of resonance; input electrode means in contact with one of said principal areas of resonance and output electrode means in contact with the other of said principal areas of resonance; and at least a portion of a first composite thickness of said body of piezoelectric material, said activating material and one of said input and output electrode means being an even multiple of half-wavelengths of a predetermined frequency and at least a portion of a second composite thickness of said body, said activating material and the other of said input and output electrode means being an odd multiple of half-wavelengths of substantially said same predetermined frequency.

Claim 10

The piezoelectric resonating device of claim 7 wherein said body is formed of zinc oxide.

Claim 11

The piezoelectric resonating device of claim 8 wherein said active material forming said principal area of resonance is lithium.

Claim 12

The piezoelectric resonating device of claim 7 wherein said at least one pair of principal areas of resonance are formed in said substrate spaced from one another a first predetermined distance, and said first and second electrode means in contact with said principal areas of resonance are spaced from one another a second predetermined distance.

Claim 13

The piezoelectric resonating device of claim 10 Wherein the space between said electrode means over said second predetermined distance forms a capacitive coupling between said pair of principal areas of resonance.

Claim 14

The piezoelectric resonating device of claim 7 wherein said body of material is tapered uniformly from one end to the other decreasing in thickness to provide principal areas of resonance which have greater frequency response than do principal areas of resonance in the immediately adjacent thicker portion of the tapered body.

Claim 15

The piezoelectric resonating device of claim 1 including a multiplicity of pairs of principal areas of resonance formed in said body of piezoelectric material, and a corresponding multiplicity of current control devices each having load electrodes and a control electrode, said control electrode being coupled to the output electrode of a corresponding associated one of said principal areas of resonance.

Claim 16

The piezoelectric resonating device of claim 13 wherein said body of piezoelectric material is tapered uniformly from one end to the other and immediately adjacent pairs of principal areas of resonance are coupled to the control electrode of a corresponding one of said current control devices.

Claim 17

The piezoelectric resonating device of claim 7 wherein the composite thickness of said body of material, said activating material for said one principal area of resonance, and said input electrode is an even multiple of half-wavelengths of said predetermined frequency and the composite thickness of said body of material, said activating material for said other of said principal areas of resonance, and said output electrode is an odd multiple of half-wavelengths of said same predetermined frequency.

Claim 18

The combination according to claim 7 wherein each of said first and second composite thicknesses includes a portion which is an even multiple of half-wavelengths of said predetermined frequency and another portion which is an odd multiple of half-wavelengths of said predetermined frequency.

Claim 19

The piezoelectric resonating device according to claim 15 wherein the thickness of the major portion of said body of piezoelectric material is such as to form said first and second composite thicknesses as an odd multiple of half-wavelengths of said predetermined frequency and said portions of said first and second composite thicknesses which is an even multiple of half-wavelengths of said predetermined frequency is formed by circular undercut portions located beneath each of said input and output electrode means.