Flexible high performance microbolometer detector material fabricated via controlled ion beam sputter deposition process

• US 6,495,070 B1
• Filed: 12/30/1998
• Issued: 12/17/2002
• Est. Priority Date: 12/31/1996
• Status: Expired due to Term

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Zins, Christopher J., Cole, Barrett E.
• Primary Examiner(s): KOPEC, MARK T
• Application Number:
  US09/222,649
• Time in Patent Office: 1,448 Days
• Field of Search: 252/518.1, 252/519.1, 252/520.4, 423/62, 423/592
• US Class Current: 252/520.4
• CPC Class Codes: C23C 14/083 of refractory metals or yttrium
• CPC Class Codes: C23C 14/46 by ion beam produced by an external ion source
• CPC Class Codes: G01J 5/20 using resistors, thermistors or semiconductors sensitive to radiation, e.g. photoconductive devices

Abstract

A microbolometer film material VOx having a value such that the thermal coefficient of resistance is between 0.005 and 0.05. The film material may be formed on a wafer. The VOx material properties can be changed or modified by controlling certain parameters in the ion beat sputter deposition environment. There is sufficient control of the oxidation process to permit non-stoichometric formation of VOx films. The process is a low temperature process (less than 100 degrees C.). Argon is used for sputtering a target of vanadium in an environment wherein the oxygen level is controlled to determine the x of VOx. The thickness of the film is controlled by the time of the deposition. Other layers may be deposited as needed to form pixels for a bolometer array.

Claims

1. A VOx material comprising vanadium and oxygen forming respective portions of the VOx material, wherein x is a value selected to determine a thermal coefficient of resistance (TCR) of between 0.005°

C.<sup>−

1</sup> and 0.05°

C<sup>−

1</sup>.

2. The VOx material of claim 1, wherein the relationship between VOx material resistance and TCR is provided by the relationship TCR=A+B*log(rho), where A and B are numerical constants.

3. The VOx material of claim 2, wherein:

A is between 0.005 and 0.05; and

B is between 0.1 and 0.001.

4. A VOx material comprising vanadium and oxygen, the material having a thermal coefficient of resistance (TCR) of between 0.005 and 0.05°

C.<sup>−

1</sup> and a log of conductivity between zero and three.

5. The VOx material of claim 4, wherein the TCR is between 0.005 and 0.03°

C.<sup>−

1</sup>.

6. The VOx material of claim 4, the material further having a resistivity (rho), wherein the relationship between TCR and resistivity (rho) is generally defined by the equation TCR=A+B*log(rho), where A and B are numerical constants.

7. The VOx material of claim 6, wherein:

A is between 0.005 and 0.05; and

B is between 0.001 and 0.1.