THz WAVE DETECTOR

• US 20110108729A1
• Filed: 10/14/2010
• Published: 05/12/2011
• Est. Priority Date: 11/12/2009
• Status: Active Grant

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: ODA, NAOKI
• Granted Patent: US 8,513,606 B2
• Time in Patent Office: Days
• US Class Current: 250/338.4
• CPC Class Codes: H01L 27/14601 Structural or functional details thereof
• CPC Class Codes: H01L 27/14649 Infrared imagers

Abstract

A THz wave detector including a thermal isolation structure in which a supporting unit containing electrode wirings connected to a readout circuit formed in an substrate supports a temperature detecting unit connected to the electrode wirings so that one face of said temperature detecting unit and said substrate are opposed to each other with a predetermined gap, wherein a reflective film reflecting THz waves is formed on the substrate so as to face the temperature detecting unit, an absorbing film absorbing the THz waves is formed on the temperature detecting unit, the reflective film and the temperature detecting unit form an optical resonant structure, the distance between the reflective film and the temperature detecting unit is set to 8 to 14 μm, and the sheet resistance of the absorbing film is set to 100 to 200 Ω/square.

Claims

1. A THz wave detector comprising a thermal isolation structure in which a supporting unit containing electrode wirings connected to a readout circuit formed in a substrate supports a temperature detecting unit connected to said electrode wirings so that one face of said temperature detecting unit and said substrate are opposed to each other with a predetermined gap, wherein:

a reflective film reflecting THz waves is formed on said substrate so as to face said temperature detecting unit, an absorbing film absorbing said THz waves is formed on said temperature detecting unit, and said reflective film and said temperature detecting unit form an optical resonant structure; and

the distance between said reflective film and said temperature detecting unit is set to 8 to 14 μ

m and the sheet resistance of said absorbing film is set to 100 to 200 Ω

/square.

2. The THz wave detector according to claim 1 wherein a canopy extending outward from the periphery of said temperature detecting unit is formed on said temperature detecting unit, said absorbing film is formed on said temperature detecting unit and on said canopy, the distance between said reflective film and said temperature detecting unit and the distance between said reflective film and said canopy are set to 8 to 14 μ

m and the sheet resistance of said absorbing film is set to 100 to 200 Ω

/square.

3. The THz wave detector according to claim 1 wherein said temperature detecting unit includes a bolometer thin film connected to said electrode wirings.

4. The THz wave detector according to claim 2 wherein said temperature detecting unit includes a bolometer thin film connected to said electrode wirings.

5. The THz wave detector according to claim 1 wherein said distance and said sheet resistance are set so that the absorptance for THz waves in a wavelength range from 30 to 300 μ

m is 20% or higher.

6. The THz wave detector according to claim 2 wherein said distance and said sheet resistance are set so that the absorptance for THz waves in a wavelength range from 30 to 300 μ

m is 20% or higher.

7. The THz wave detector according to claim 3 wherein said distance and said sheet resistance are set so that the absorptance for THz waves in a wavelength range from 30 to 300 μ

m is 20% or higher.

8. The THz wave detector according to claim 4 wherein said distance and said sheet resistance are set so that the absorptance for THz waves in a wavelength range from 30 to 300 μ

m is 20% or higher.

9. The THz wave detector according to claim 2 wherein said canopy is made of silicon nitride.

10. The THz wave detector according to claim 4 wherein said canopy is made of silicon nitride.

11. The THz wave detector according to claim 6 wherein said canopy is made of silicon nitride.

12. The THz wave detector according to claim 8 wherein said canopy is made of silicon nitride.

13. A THz wave detector comprising a thermal isolation structure in which a supporting means containing electrode wirings connected to a readout circuit formed in a substrate supports a temperature detecting means connected to said electrode wirings so that one face of said temperature detecting means and said substrate are opposed to each other with a predetermined gap, wherein:

a reflecting means reflecting THz waves is formed on said substrate so as to face said temperature detecting means, an absorbing means absorbing said THz waves is formed on said temperature detecting means, and said reflective means and said temperature detecting means form an optical oscillation means; and

the distance between said reflective means and said temperature detecting means is set to 8 to 14 μ

m and the sheet resistance of said absorbing means is set to 100 to 200 Ω

/square.

14. A manufacturing method of a THz wave detector comprising a thermal isolation structure in which a supporting unit containing electrode wirings connected to a readout circuit formed in a substrate supports a temperature detecting unit connected to said electrode wirings so that one face of said temperature detecting unit and said substrate are opposed to each other with a predetermined gap, wherein:

a reflective film reflecting THz waves is formed on said substrate so as to face said temperature detecting unit, an absorbing film absorbing said THz waves is formed on said temperature detecting unit, and said reflective film and said temperature detecting unit form an optical resonant structure; and

the distance between said reflective film and said temperature detecting unit is set to 8 to 14 μ

m and the sheet resistance of said absorbing film is set to 100 to 200 Ω

/square.