Methods of manufacture for electronic components having high-frequency elements

A production method of a high-frequency apparatus using a quartz crystal resonator, comprising the steps of:

• treating a semiconductor substrate at a temperature of 570.degree. C. or more;
• bonding a quartz crystal plate directly to said semiconductor substrate;
• removing said semiconductor substrate only in a part of an area just beneath said quartz crystal plate leaving an area necessary to hold said quartz crystal by an etching method to form a quartz crystal resonator;
• and
• treating said semiconductor substrate having the quartz crystal resonator directly bonded thereto at a temperature of 560.degree. C. or less, whereby a transistor and said quartz crystal resonator are integrated in a unitary body therewith.

A production method of a high-frequency apparatus using a quartz crystal resonator, comprising the steps of:

• treating a semiconductor substrate at a temperature of 570.degree. C. or more;
• bonding a quartz crystal plate directly to said semiconductor substrate;
• processing said quartz crystal plate so as to have a thickness of 5 .mu.m or less and removing said semiconductor substrate only in a part of an area just beneath said quartz crystal plate leaving an area necessary to hold said quartz crystal plate by applying an etching method from a surface of said semiconductor substrate opposite to a surface on which said quartz crystal plate is bonded to form a quartz crystal resonator;
• and
• treating said semiconductor substrate having the quartz crystal resonator directly bonded thereto at a temperature of 560.degree. C. or less.

A manufacturing method of an electro-acoustic hybrid integrated circuit, comprising the steps of:

• providing a semiconductor substrate;
• providing a single crystalline piezoelectric substrate;
• performing processes necessary for forming an active element on said semiconductor substrate at processing temperatures higher than the heat treatment temperature for direct bonding;
• forming a film including silicon on at least one of said semiconductor substrate and said piezoelectric substrate;
• bonding said semiconductor substrate directly with said piezoelectric substrate via said film;
• and
• performing processes for forming the active element and the metallization at a processing temperature lower than the heat treatment temperature for direct bonding and processes for forming a surface acoustic wave element on said piezoelectric substrate;
• whereby an active element and the surface acoustic wave element are integrated as one body.

A manufacturing method of an electro-acoustic hybrid integrated circuit, comprising the steps of:

• providing a semiconductor substrate made from a III-V compound;
• providing a quartz plate;
• performing processes necessary for forming an active element on said semiconductor substrate at processing temperatures higher than a heat treatment temperature for direct bonding;
• forming a film including silicon on at least one of said semiconductor substrate and said quartz plate;
• bonding said semiconductor substrate directly with said quartz plate via said film;
• forming a throughhole in said semiconductor substrate to reach and expose the back surface of said quartz plate, which back surface is bonded with said semiconductor substrate;
• and
• performing processes for forming the active element and the metallization at a processing temperature lower than the heat treatment temperature for direct bonding and processes for forming a quartz oscillator on the quartz plate;
• whereby the active element and the quartz oscillator are integrated as one body.

A method for making a quartz device comprising a quartz crystal plate made of quartz and having first and second surfaces, a first excitation electrode deposited on the first surface of the quartz plate, a second excitation electrode deposited on the second surface of the quartz plate opposing the first excitation electrode, and a holding member having a surface which is held by means of direct bonding to a surface of the quartz plate, said method comprising the steps of:

• (a) cleaning said quartz crystal plate and said holding member;
• (b) hydrophilically treating the bonding surfaces;
• (c) holding and contacting the bonding surfaces together;
• and
• (d) applying a heat treatment.

A method for making a quartz device comprising a quartz crystal plate made of quartz and having first and second surfaces, a first excitation electrode deposited on the first surface of the quartz plate, a second excitation electrode deposited on the second surface of the quartz plate opposing the first excitation electrode, and a holding member having a surface which is held by means of direct bonding to a surface of the quartz plate, said method comprising the steps of:

• (a) cleaning said quartz crystal plate and said holding member;
• (b) holding and contacting the bonding surfaces together;
• and
• (c) applying a voltage between said bonding surfaces.

A method for making plural quartz devices, each of which comprises a quartz plate made of quartz and having first and second surfaces, a first excitation electrode deposited on the first surface of the quartz plate, a second excitation electrode deposited on the second surface of the quartz plate opposing the first excitation electrode, and a holding member having a recess, a portion of the quartz plate being connected to the holding member by direct bonding, and a major portion of the quartz plate which is subject to vibration hanging over the recess of the holding member, said method comprising the steps of:

• (a) providing a quartz wafer;
• (b) depositing said second excitation electrodes on said quartz wafer;
• (c) providing a holding member bulk;
• (d) connecting said quartz wafer and said holding member bulk by direct bonding;
• (e) lapping said quartz wafer;
• (f) depositing said first excitation electrodes on lapped surfaces of said quartz wafer;
• and
• (g) cutting said holding member bulk into individual quartz devices.

A method for making plural quartz devices, each of which comprises a quartz plate made of quartz and having first and second surfaces, a first excitation electrode deposited on the first surface of the quartz plate, a second excitation electrode deposited on the second surface of the quartz plate opposing the first excitation electrode, and a holding member having a recess, a portion of the quartz plate being connected to the holding member by direct bonding, and a major portion of the quartz plate which is subject to vibration hanging over the recess of the holding member, said method comprising the steps of:

• (a) providing a quartz wafer with plural rectangular projections;
• (b) depositing said second excitation electrodes on surfaces of said rectangular projections;
• (c) providing a holding member bulk having plural recesses at positions corresponding to said plural rectangular projections;
• (d) depositing said first and second terminal electrodes onto said holding member bulk;
• (e) connecting said quartz wafer and said holding member bulk by direct bonding effected between a portion of each of said rectangular projections and a portion adjacent each of said recesses;
• (f) lapping said quartz wafer to form said quartz plates;
• (g) depositing said first excitation electrodes on lapped surfaces of said quartz plates;
• and
• (h) cutting said holding member bulk into individual quartz devices.

A method for making plural quartz devices, each of which comprises a quartz plate made of quartz and having first and second surfaces, a first excitation electrode deposited on the first surface of the quartz plate, a second excitation electrode deposited on the second surface of the quartz plate opposing the first excitation electrode, a holding member comprising a plate, and a housing substrate having a recess, a portion of the quartz plate being connected to a portion of the holding member by direct bonding, a portion of the holding member being connected to a portion of the housing substrate by direct bonding, and a major portion of the quartz plate which is subject to vibration hanging over the recess of the housing substrate, said method comprising the steps of:

• (a) providing a quartz wafer;
• (b) providing a holding member bulk;
• (c) connecting said quartz wafer and said holding member bulk by direct bonding;
• (d) lapping said holding member bulk;
• (e) depositing said second excitation electrodes on surfaces of said quartz wafer and also on said holding member bulk;
• (f) providing a housing substrate bulk;
• (g) connecting said holding member bulk and said housing substrate bulk by direct bonding;
• (h) lapping said quartz wafer;
• (i) depositing said first excitation electrodes on lapped surfaces of said quartz wafer;
• and
• (j) cutting said housing substrate bulk into individual quartz devices.

A method for making plural quartz devices, each of which comprises a quartz plate made of quartz and having first and second surfaces, a first excitation electrode deposited on the first surface of the quartz plate, a second excitation electrode deposited on the second surface of the quartz plate opposing the first excitation electrode, a holding member comprising a plate, and a housing substrate having a recess, a portion of the quartz plate being connected to a portion of the holding member by direct bonding, a portion of the holding member being connected to a portion of the housing substrate by direct bonding, and a major portion of the quartz plate which is subject to vibration hanging over the recess of the housing substrate, said method comprising the steps of:

• (a) providing a quartz wafer having plural rectangular projections;
• (b) providing a holding member bulk having plural rectangular projections;
• (c) connecting said quartz wafer and said holding member bulk by direct bonding effected between a portion of each of said rectangular projections of said quartz wafer and a portion of each of said rectangular projections of said holding member bulk;
• (d) lapping said holding member bulk to form said holding members;
• (e) depositing said second excitation electrodes on surfaces of said rectangular projections of said quartz wafer and also on said holding members;
• (f) providing a housing substrate bulk having plural recesses at positions corresponding to said plural rectangular projections of said quartz wafer;
• (g) depositing said first and second terminal electrodes to said housing substrate bulk;
• (h) connecting said holding members and said housing substrate bulk by direct bonding effected between a portion of each of said holding members and a portion of said housing substrate bulk adjacent each of said recesses;
• (i) lapping said quartz wafer to form said quartz plates;
• (j) depositing said first excitation electrodes on lapped surfaces of said quartz plates;
• and
• (k) cutting said housing substrate bulk into individual quartz devices.

A method of producing a piezoelectric filter, comprising the steps of:

• subjecting surfaces of an oscillatory piezoelectric plate and a glass plate for holding the piezoelectric plate, to a hydrophilic treatment;
• the piezoelectric plate being made of one of quartz, lithium tantalate, lithium niobate and lithium borate;
• bringing the surfaces of the piezoelectric plate and the glass plate into contact with each other;
• and
• subjecting the piezoelectric plate and the glass plate to a heat treatment at a temperature such that the piezoelectric plate and the glass plate are directly bonded to each other;
• the temperature being lower than a lower one of a temperature leading to exhibition of a piezoelectric property by the piezoelectric plate even after the heat treatment and a softening point of glass of the glass plate.

A method of producing a piezoelectric filter, comprising the steps of:

• subjecting surfaces of an oscillatory piezoelectric plate and a silicon plate for holding the piezoelectric plate, to a hydrophilic treatment;
• the piezoelectric plate being made of one of quartz, lithium tantalate, lithium niobate and lithium borate;
• bringing the surfaces of the piezoelectric plate and the silicon plate into contact with each other;
• and
• subjecting the piezoelectric plate and the silicon plate to a heat treatment at a temperature such that the piezoelectric plate and the silicon plate are directly bonded to each other;
• the temperature being lower than a temperature leading to exhibition of piezoelectric property by the piezoelectric plate even after the heat treatment.

A method of producing a piezoelectric filter, comprising the steps of:

• subjecting surfaces of an oscillatory piezoelectric plate and a plate for holding the piezoelectric plate, to a hydrophilic treatment;
• the piezoelectric plate being made of one of quartz, lithium tantalate, lithium niobate and lithium borate;
• the plate being made of one of quartz, lithium tantalate, lithium niobate and lithium borate;
• bringing the surfaces of the piezoelectric plate and the plate into contact with each other;
• and
• subjecting the piezoelectric plate and the plate to a heat treatment at a temperature such that the piezoelectric plate and the plate are directly bonded to each other;
• the temperature being lower than a temperature leading to exhibition of a piezoelectric property by the piezoelectric plate even after the heat treatment.

A method of producing a piezoelectric filter by providing silicon or silicon compound on one of opposed surfaces of an oscillatory piezoelectric plate and a glass plate for holding the piezoelectric plate, the method comprising the steps of:

• subjecting a surface of the silicon or the silicon compound and the other of the opposed surfaces of the piezoelectric plate and the glass plate to a hydrophilic treatment;
• the piezoelectric plate being made of one of quartz, lithium tantalate, lithium niobate and lithium borate;
• bringing the surface of the silicon or the silicon compound and the other of the opposed surfaces of the piezoelectric plate and the glass plate into contact with each other;
• and
• subjecting the piezoelectric plate and the glass plate to a heat treatment at a temperature such that the piezoelectric plate and the glass plate are directly bonded to each other by the silicon or the silicon compound;
• the temperature being lower than a lower one of a temperature leading to exhibition of a piezoelectric property by the piezoelectric plate even after the heat treatment and a softening point of glass of the glass plate.

A method of producing a piezoelectric filter by providing silicon or silicon compound on one of opposed surfaces of an oscillatory piezoelectric plate and a silicon plate for holding the piezoelectric plate, the method comprising the steps of:

• subjecting a surface of the silicon or the silicon compound and the other of the opposed surfaces of the piezoelectric plate and the silicon plate to a hydrophilic treatment;
• the piezoelectric plate being made of one of quartz, lithium tantalate, lithium niobate and lithium borate;
• bringing the surface of the silicon or the silicon compound and the other of the opposed surfaces of the piezoelectric plate and the silicon plate into contact with each other;
• and
• subjecting the piezoelectric plate and the silicon plate to a heat treatment at a temperature such that the piezoelectric plate and the silicon plate are directly bonded to each other by the silicon or the silicon compound;
• the temperature being lower than a temperature leading to exhibition of a piezoelectric property by the piezoelectric plate even after the heat treatment.

A method of producing a piezoelectric filter by providing silicon or silicon compound on one of opposed surfaces of an oscillatory piezoelectric plate and a plate for holding the piezoelectric plate, the method comprising the steps of:

• subjecting a surface of the silicon or the silicon compound and the other of the opposed surfaces of the piezoelectric plate and the plate to a hydrophilic treatment;
• the piezoelectric plate being made of one of quartz, lithium tantalate, lithium niobate and lithium borate;
• the plate being made of one of quartz, lithium tantalate, lithium niobate and lithium borate;
• bringing the surface of the silicon or the silicon compound and the other of the opposed surfaces of the piezoelectric plate and the plate into contact with each other;
• and
• subjecting the piezoelectric plate and the plate to a heat treatment at a temperature such that the piezoelectric plate and the plate are directly bonded to each other by the silicon or the silicon compound;
• the temperature being lower than a temperature leading to exhibition of a piezoelectric property by the piezoelectric plate even after the heat treatment.

A production method of an electronic component comprising:

• providing a substrate;
• providing a high-frequency element;
• and
• bonding said high-frequency element to said substrate via direct bonding.