Microwave integrated circuit

Claim 2

A hybrid microwave integrated circuit including a microwave transmission line having a conducting film strip and a metallic ground plane and at least one microwave semiconductor device directly connected to the conducting film strip anD virtually connected to the metallic ground plane instead of an actual connection to the ground plane for operation at a predetermined frequency band comprising: said metallic ground plane, said conducting film strip, an insulating substrate bonded at one surface to said metallic ground plane and bonded at the other surface to said conducting film strip, a tunable film stub bonded to said other surface of said substrate and having an input end forming a gap with said metallic strip conductor, said microwave semiconductor device including lead means being mounted on said other side of said substrate and being connected between said conducting film strip and said input of said tunable film stub, said tunable film stub being essentially one-quarter wave length long at the center of said frequency band and having another end which is open circuited, whereby said input end and the lead of said microwave conductor device connected thereto see a short circuit and consequently see a virtual connection to said ground plane at said frequency band, said lead means having a certain reactance, and the length of said tunable stub providing a reactance value such as to be tuned with the reactance of said lead means.

Claim 3

A microwave circuit according to claim 1 wherein said microwave semiconductor device is an unpackaged diode.

Claim 4

A microwave circuit according to claim 2 wherein said semiconductor device is a PIN diode.

Claim 5

A microwave circuit according to claim 2 wherein said microwave semiconductor device is a Schottky barrier diode.

Claim 6

A microwave circuit according to claim 2 wherein said diode is operated in a forward biased direction.

Claim 7

A microwave circuit according to claim 2 wherein said diode is operated in a reverse bias direction and having a certain reactance and, a second tunable film stub bonded to said other surface of said substrate and having an input end connected to said conducting film strip adjacent the connection thereto of one lead of said microwave semiconductor diode, said second tunable film stub being essentially one-half wave length long at the center of said frequency band and having another end which is open circuited, whereby said input end of said second film stub and the lead of said diode connected thereto see an open circuit at said frequency band, and the length of said second tunable stub provides a reactance value such as to be tuned with said certain reactance of said diode.

Claim 8

The microwave integrated circuit according to claim 3 wherein said PIN diode includes beam leads.

Claim 9

The microwave integrated circuit according to claim 1 wherein the reactance of the lead means is inductive and the reactance of said tunable stub is capacitive.

Claim 10

The microwave integrated circuit according to claim 6 wherein the reactance of said diode is capacitive and the reactance of said second tunable stub is inductive.

Claim 11

The microwave integrated circuit according to claim 1 wherein the said tuning is substantially a series resonance.

Claim 12

The microwave integrated circuit according to claim 6 wherein the said tuning is substantially a parallel resonance.

Claim 13

A hybrid microwave integrated circuit including a microwave transmission line having a conducting film strip and a metallic ground plane and at least one microwave semiconductor diode directly connected to the conducting film strip and virtually connected to the ground plane instead of an actual connection to the ground plane for operation at a predetermined frequency band comprising: said metallic ground plane, said conducting film strip, an insulating substrate bonded at one surface to said metallic ground plane and bonded at the other surface to said conducting film strip, a first tunable film stub bonded to said other surface of said substrate and having an input end forming a gap with said metallic strip conductor, said microwave semiconductor diode including lead means being mounted On said other side of said substrate, and having its lead means connected between said conducting film strip and said input of said first tunable stub, said first tunable film stub being essentially one-quarter wave length long at the center of said frequency band and having another end which is open circuited, whereby said input end and the lead of said microwave semiconductor diode connected thereto see a short circuit and consequently see a virtual connection to said metallic ground plane at said frequency band, said lead means having a certain inductive reactance, and the length of said tunable stub providing a capacitive reactance value such as to substantially series resonate with the inductive reactance of said lead means, said microwave semiconductor diode being operated in a reverse biased direction and having a certain capacitive reactance, and a second tunable film stub bonded to said other surface of said substrate and having an input end connected to said conducting film strip adjacent the connection thereto of one terminal of said microwave semiconductor diode, said second tunable film stub being essentially one-half wave length long at the center of said frequency band and having another end which is open circuited, whereby said input end of said second film stub and the lead of said microwave semiconductor diode see an open circuit at said frequency band, and the length of said second tunable stub providing an inductive reactance value such as to substantially parallel resonate with said capacitive reactance of said diode.

Claim 14

A hybrid microwave integrated circuit including a microwave transmission line having a conducting film strip and a metallic ground plane and at least one microwave semiconductor diode directly connected to the conducting film strip and virtually connected to the ground plane instead of an actual connection to the ground plane for operation at a predetermined frequency band comprising: said metallic ground plane, said conducting film strip, an insulating substrate bonded at one surface to said metallic ground plane and bonded at the other surface to said conducting film strip, a first tunable film stub bonded to said other surface of said substrate and having an input end forming a gap with said metallic strip conductor, said microwave semiconductor diode including lead means being mounted On said other side of said substrate, and having its lead means connected between said conducting film strip and said input of said first tunable stub, said first tunable film stub being essentially one-quarter wave length long at the center of said frequency band and having another end which is open circuited, whereby said input end and the lead of said microwave semiconductor diode connected thereto see a short circuit and consequently see a virtual connection to said metallic ground plane at said frequency band, said lead means having a certain inductive reactance, and the length of said tunable stub providing a capacitive reactance value such as to substantially series resonate with the inductive reactance of said lead means, said microwave semiconductor diode being operated in a reverse biased direction and having a certain capacitive reactance, and a second tunable film stub bonded to said other surface of said substrate and having an input end connected to said conducting film strip adjacent the connection thereto of one terminal of said microwave semiconductor diode, said second tunable film stub being essentially one-half wave length long at the center of said frequency band and having another end which is open circuited, whereby said input end of said second film stub and the lead of said microwave semiconductor diode see an open circuit at said frequency band, and the length of said second tunable stub providing an inductive reactance value such as to substantially parallel resonate with said capacitive reactance of said diode.

Claim 15

In a hybrid microwave integrated circuit including a microwave transmission line having a conducting film strip and a metallic ground plane and at least one microwave semiconductor device directly connected to the conducting film strip and virtually connected to the ground plane instead of an actual connection to the ground plane for operation at a predetermined frequency band comprising: said metallic ground plane, said conducting film strip bonded to other surface of said substrate, an insulated substrate bonded at one surface to said metallic ground plane and bonded at the other surface to said conducting film strip, a first tunable film stub bonded to said other surface of said substrate and having an input end forming a gap with said metallic strip conductor, said microwave semiconductor device including lead means being mounted on said other side of said substrate and having its lead means connected between said conducting film strip and said input of said first tunable film stub, said first tunable film stub being essentially one-quarter wave length long at the center of said frequency band and having another end which is open circuited, whereby said input end and the lead of said microwave semiconductor diode connected thereto see a short circuit and consequently see a virtual connection to a metallic ground plane at said frequency band, said lead means having a certain value of inductive reactance, said microwave semiconductor device having a certain value of capacitive reactance, a second tunable film stub bonded to said other surface of said substrate and having an input end connected to said conducting film strip adjacent the connection thereto of the lead means of said microwave semiconductor device; the method of tuning out the effects of the inductive reactance of said lead means which comprises shortening the length of said first tunable film stub to less than one-quarter of a wave length at said frequency band to give a capacitive reactance such as to substantially series resonate with the inductive reactance of said lead means, and thereafter shortening the length of said second tunable film stub to less than one-half of a wave length at said frequency band to give an inductive reactance such as to substantially parallel resonate with the capacitive reactance of said semiconductive device.

Claim 16

In a hybrid microwave integrated circuit including a microwave transmission line having a conducting film strip and a metallic ground plane and at least one microwave semiconductor device directly connected to the conducting film strip and virtually connected to the ground plane instead of an actual connection to the ground plane for operation at a predetermined frequency band comprising: said metallic ground plane, said conducting film strip bonded to other surface of said substrate, an insulated substrate bonded at one surface to said metallic ground plane and bonded at the other surface to said conducting film strip, a first tunable film stub bonded to said other surface of said substrate and having an input end forming a gap with said metallic strip conductor, said microwave semiconductor device including lead means being mounted on said other side of said substrate and having its lead means connected between said conducting film strip and said input of said first tunable film stub, said first tunable film stub being essentially one-quarter wave length long at the center of said frequency band and having another end which is open circuited, whereby said input end and the lead of said microwave semiconductor diode connected thereto see a short circuit and consequently see a virtual connection to a metallic ground plane at said frequency band, said lead means having a certain value of inductive reactance, said microwave semiconductor device having a certain value of capacitive reactance, a second tunable film stub bonded to said other surface of said substrate and having an input end connected to said conducting film strip adjacent the connection thereto of the lead means of said microwave semiconductor device; the method of tuning out the effects of the inductive reactance of said lead means which comprises shortening the length of said first tunable film stub to less than one-quarter of a wave length at said frequency band to give a capacitive reactance such as to substantially series resonate with the inductive reactance of said lead means, and thereafter shortening the length of said second tunable film stub to less than one-half of a wave length at said frequency band to give an inductive reactance such as to substantially parallel resonate with the capacitive reactance of said semiconductive device.

Claim 17

The microwave integrated circuit according to claim 12 wherein a one-quarter wave length film strip of one characteristic impedance in series with a second one-quarter wave length stub of a lesser characteristic impedance are formed on said surface of said substrate, the front end of said film strip is connected to the front end of said first tunable film stub, and the back end of said second one-quarter wave length stub is open circuited on a distributed constant basis, a DC bias input connection is provided between the junctions of said film strip and said second one-quarter wave length stub on said other surface of said substrate, and a DC bias return film is formed on said other surface of said substrate comprising a narrow one-quarter wave length strip joined to said transmission line and terminating in a third one-quarter wave length stub, the junction between said narrow strip and said third one-quarter wave length stub being grounded, and the end of said third one-quarter wave length stub being open circuited.