Temperature dependence of sensor leakage current

Temperature dependence of sensor leakage current

Contents

•Introduction

•Measurement

•Result

•Summary

Junkichi Asai (RIKEN BNL Research Center)

(Hiroki kanoh (Tokyo Institute of Technology))

VTX Meeting 6/1/2004

Introduction

Tk

EATTI

B

g

2exp)( 2

::::

B

g

kEAT Temperature

sensor constant Energy gap =1.2 boltzmann constant

VI

::::

V

I Increase dark current damage constant [A/cm] sensor Volume [cm3] radiation flux [/cm2]

• Silicon breaks by Radiation damage:

dark current increases

• Main part of dark current is leakage current depending on temperature:

Setup

• Silicon strip sensor : 1st prototype detector

(2002 Nov : Test beam at KEK)

Currents

Voltage

Thickness: 400um

Channel: 384x384 (sum : 768 strips)

Front

Back

SensorAmmeter Voltage

Setup• device :

Senso

r

•Model 6487 Picoammeter/Voltage Source(Keithley Instruments) Voltage : as high as 500V Currents : as low as 20fA

•DAQ controlled by LabVIEW7 (programming by H. Kanoh)PC : Windows Connect : PCI-GPIB

•Temperature and Humidity controlled chamber(ESPEC LHU-113) T: -20 to 85oC (%RH : 0 to 95%)

Curren

ts

Voltag

e

PC

Front Back

Chamber

Ammeter Voltage

ChamberPCSensor Box

Measuring condition

•Sensor : In the chamber dark room keeping over 1day(for light sensitive)

•IV measurement : bulk=768 strips (not channel by channel)Bias Voltage : 0 ~ 500VCurrent : max 2mATemperature : -10 ~ 30 oCHumidity : 15% , 30%

Result (temperature dependence)

1.E- 10

1.E- 09

1.E- 08

1.E- 07

1.E- 06

1.E- 05

1.E- 04

1.E- 03

1.E- 02

1 10 100 1000

30℃25℃20℃15℃10℃5℃0℃-5℃-10℃

Bias Voltage [V]

Lea

kage

cur

rent

[A

]

Humidity : 30%

1.0E- 10

1.0E- 09

1.0E- 08

1.0E- 07

1.0E- 06

1.0E- 05

1.0E- 04

1.0E- 03

1.0E- 02

260 270 280 290 300

500V400V320V250V200V160V100V50V25V1V

Result (temperature dependence)L

eaka

ge c

urre

nt [

A]

[k]

Temperature

Bias Voltage

Humidity : 30%

-10 -5 0 5 10 15 20 25 30 [oC]

100Vconstant

Test beam @KEK : 80~90 V

@100V

T[oC]

I[uA]

30 70

25 51

20 32

15 20

10 15

5 10

0 8

-5 9

-10 9

Result (humidity dependence)

Bias Voltage [V]

[A]

1.0E-09

1.0E-08

1.0E-07

1.0E-06

1.0E-05

1.0E-04

1.0E-03

0 50 100 150 200

20℃ 30%20℃ 15%10℃ 30%10℃ 15%L

eaka

ge c

urre

nt

[A]

Summary

• RIKEN facility activity• Study temperature dependence of silicon leakage current• Silicon strip sensor : 1st prototype detector

thickness 400um, 768 strips

• Measurement : Bias Voltage 0~500 [V]temperature -10~30 [oC]

Humidity 15, 30 [%]

• Best operating temperature : 10oC, 15uA@100V