Semiconductor device with a filter formed of 3-element series-and-parallel resonators

• US 5,697,087 A
• Filed: 10/24/1995
• Issued: 12/09/1997
• Est. Priority Date: 01/25/1993
• Status: Expired due to Fees

• Current Assignee: NEC Electronics Corporation (Renesas Electronics Corporation)
• Original Assignee: NEC Corporation
• Inventors: Noguchi, Tsutomu, Miya, Tatsuya
• Primary Examiner(s): Urban, Edward F.
• Application Number:
  US08/547,428
• Time in Patent Office: 777 Days
• Field of Search: 455/291, 455/292, 455/293, 455/302, 455/307, 455/333, 455/339, 455/252.1, 455/289, 333/175, 333/181, 333/184, 333/185, 333/204, 333/219
• US Class Current: 455/307
• CPC Class Codes: H03D 7/18 Modifications of frequency-changers for eliminating image frequencies H03D7/16 takes precedence
• CPC Class Codes: H03H 2001/0064 comprising semiconductor material
• CPC Class Codes: H03H 2001/0078 comprising spiral inductor on a substrate
• CPC Class Codes: H03H 7/0115 comprising only inductors and capacitors H03H7/075, H03H7/09, H03H7/12, H03H7/13 take precedence
• CPC Class Codes: H03H 7/175 Series LC in series path H03H7/1783 takes precedence
• CPC Class Codes: H03H 7/1758 Series LC in shunt or branch path H03H7/1791 takes precedence
• CPC Class Codes: H03H 7/1766 Parallel LC in series path H03H7/1783 takes precedence
• CPC Class Codes: H03H 7/1775 Parallel LC in shunt or branch path H03H7/1791 takes precedence
• CPC Class Codes: H03H 7/1783 Combined LC in series path
• CPC Class Codes: H03H 7/1791 Combined LC in shunt or branch path

Abstract

A 3-element series parallel resonator, which performs series resonance and parallel resonance at a predetermined frequency by a combination of three elements including an inductor and a capacitor of concentrated constants, is used as a filter. This design can reduce the circuit constant and permits a filter to be formed on a semiconductor substrate. Accordingly, various micro-wave devices, such as an amplifier which requires a filter, a frequency converter, a multiplier and signal switcher, can be designed into an MMIC on a single chip.

Claims

1. A semiconductor device comprising an amplifier for amplifying an input signal and generating an amplified signal, a conductor line connected to said amplifier to transmit said amplified signal, an oscillator for generating a local oscillation signal, a mixer, coupled to said conductor line to receive said amplified signal therefrom and to said oscillator to receive said oscillation signal therefrom, for producing an intermediate frequency signal, and a resonator connected between said conductor line and a reference potential line, said resonator being a 3-element serial-and-parallel resonator including an inductor and at least one capacitor and constructed for performing a series resonance and a parallel resonance at a predetermined frequency of said amplified signal,

wherein said resonator includes said inductor, a first capacitor and a second capacitor, and further includes a conductive layer branching off from said conductor line, said inductor being formed as a spiral conductor having a first end connected to said conductive layer and a second end, said first capacitor including a lower electrode formed by a first conductor connected to said conductive layer, a dielectric film formed by a first insulator formed on said first conductor and an upper electrode formed by a second conductor formed on said first insulator, said second capacitor including a lower electrode formed by a third conductor connected to said second end of said spiral conductor, a dielectric film formed by a second insulator formed on said third conductor and an upper electrode formed by a fourth conductor formed on said second conductor, and a fifth conductor connected to said second and fourth conductors and extending to said reference potential line.

2. A semiconductor device comprising an amplifier for amplifying an input signal and producing an amplified signal at an output thereof, a signal conductor line having a first end portion and a second end portion, a first resonator connected between said output of said amplifier and said first end portion of said signal conductor line, a second resonator connected between said signal conductor line and a reference potential line, an oscillator for generating a local oscillation signal at an output thereof, and a mixer, coupled to said second end portion of said signal conductor line and said output of said oscillator, for producing an intermediate frequency signal, each of said first and second resonators being a 3-element serial-and-parallel resonator including an inductor and at least one capacitor and constructed for performing a series resonance and a parallel resonance at a predetermined frequency,

wherein said first resonator includes said inductor as a first inductor, said capacitor and a second inductor, and said second resonator includes said inductor, said capacitor as a first capacitor and a second capacitor;

said first resonator further includinq a first conductive layer branching off from said signal conductor line, said first inductor being formed as a spiral conductor having a first end connected to said first conductive layer and a second end, a second conductive layer branched off from said signal conductor line and connected to said first conductive layer, said second inductor being formed as a spiral conductor having a first end connected to said second conductive layer and a second end, and said capacitor being connected between said second end of said spiral conductor of said first inductor and said second end of said spiral conductor of said second inductor;

said second resonator further including a second conductive layer branching off from said signal conductor line and connected to said capacitor of said first resonator, said inductor of said second resonator being formed as a spiral conductor having a first end connected to said first conductive layer of said second resonator and a second end, said first capacitor including a lower electrode formed by a first conductor connected to said second conductive layer, a dielectric film formed by a first insulator formed on said first conductor and an upper electrode formed by a second conductor formed on said first insulator, said second capacitor including a lower electrode formed by a third conductor connected to said second end of said spiral conductor, a dielectric film formed by a second insulator formed on said third conductor and an upper electrode formed by a fourth conductor formed on said conductor, and a fifth conductor connected to said second and fourth conductors and extending to said reference potential line.