UV sensor

• US 20040135094A1
• Filed: 11/21/2003
• Published: 07/15/2004
• Est. Priority Date: 11/25/2002
• Status: Active Grant

• Current Assignee: Hamamatsu Photonics KK
• Original Assignee: Hamamatsu Photonics KK
• Inventors: Suzuki, Nobuharu, Suzuki, Yoshitaka, Niigaki, Minoru, Takagi, Yasufumi, Nakajima, Kazutoshi
• Granted Patent: US 7,217,932 B2
• Time in Patent Office: Days
• US Class Current: 250/372
• CPC Class Codes: G01J 1/429 applied to measurement of ultraviolet light using counting tubes G01T
• CPC Class Codes: H01L 2224/48465 the other connecting portion not on the bonding area being a wedge bond, i.e. ball-to-wedge, regular stitch

Abstract

A UV sensor 1 comprises a container 5 in which the upper end opening of a metal side tube 2 is sealed with a front plate 3 composed of Kovar glass as an incident light window and the lower end opening is sealed with a base plate 4. The front plate 3 serving as an incident light window constitutes part of the wall of container 5 by sealing the upper end opening of the metal side tube 2. A pin-type photodiode 6 is disposed inside the container 5. The pin-type photodiode 6 comprises a photoabsorption layer 9 formed from In_xGa_(1-x)N (0<x<1) between an n-type contact layer 8 and a p-type contact layer 10.

Claims

1. A UV sensor comprising:

an incident light window constituting part of the wall of a container; and

a pin-type photodiode disposed inside said container and employed for photoelectrically converting the light that was transmitted through said incident light window, wherein

said incident light window is composed of Kovar glass and said pin-type photodiode comprises a photoabsorption layer formed from In_xGa_(1-x)N (0<

x<

1) between an n-type nitride semiconductor layer and a p-type nitride semiconductor layer.

2. The UV sensor according to claim 1, wherein said incident light window composed of Kovar glass is formed to have a thickness of 200 μ

m or more.

3. The UV sensor according to claim 1, wherein the composition ratio x of the In_xGa_(1-x)N in said photoabsorption layer is 0<

x<

0.05.

4. The UV sensor according to claim 1, wherein the detection sensitivity of said light with a wavelength of 405 nm is not more than 1/100 of the detection sensitivity of said light with a wavelength of 365 nm.

5. The UV sensor according to claim 1, which is used as a power meter of a light source for photolithography.