VITUS Silicon Drift Detectors - KETEK GmbH€¦ · · 2017-10-19KETEK VITUS Silicon Drift Detectors (SDD) are the state-of-the-art X-ray detectors based on silicon ... damaging

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KETEK GmbH

VITUS Silicon Drift Detectors

User’s Manual

KETEK GmbH

Hofer Str. 3

81737 München

Phone +49-89-673467-70

Fax +49-89-673467-77

Steffen Pahlke

KETEK GmbH, Hofer Str. 3, D-81737 München, Germany Tel: +49-(0)89-67346770 Fax: +49-(0)89-67346777

www.ketek.net ©2012 KETEK GmbH. All rights reserved.

Rev. 6 Infor mati on furnished by KETEK is believed to be accurate and reliable. However, no r esponsibility is assumed by KETEK for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications given in this document subjec t to change without notice. No

license is granted by i mplicati on or otherwise under any patent or patent rights of KETEK. Trademar ks and registered trademarks are the property of their respective owners.

KETEK VITUS SDD Manual

Rev. 6 Page 3 of 29 KETEK GmbH

1. Table of Contents

1. Table of Contents...................................................................................................................3

2. Revision History .....................................................................................................................3

3. Features ................................................................................................................................5

4. Applications ...........................................................................................................................5

5. Functional Block Diagram .......................................................................................................5

6. General Description ...............................................................................................................5

7. Safety ...................................................................................................................................6

8. General Restrictions ...............................................................................................................7

9. Specifications ........................................................................................................................8

10. Absolute Maximum Ratings ................................................................................................9

11. Ambient Conditions .......................................................................................................... 10

12. ESD Caution.................................................................................................................... 10

13. Pin Configuration and Functional Descriptions ................................................................... 10

14. Typical Performance Characteristics ................................................................................. 11

15. Theory of Operation ......................................................................................................... 17

16. Applications and Operations Information............................................................................ 19

16.1. Wiring ......................................................................................................................... 19

16.2. Mechanical Connection ................................................................................................ 19

16.3. Readout Circuit for Temperature Sensor........................................................................ 20

16.4. Operating Voltages ...................................................................................................... 21

16.5. Preamplifier Design ...................................................................................................... 22

16.6. Peltier Characteristics .................................................................................................. 23

17. Collimator ........................................................................................................................ 25

18. Outline Dimensions .......................................................................................................... 26

19. Footprint .......................................................................................................................... 27

20. Ordering Guide ................................................................................................................ 28

21. Optional .......................................................................................................................... 28

22. Contact ........................................................................................................................... 29

2. Revision History

11/07 – Revision 0: Initial Version

12/03 – Revision 1: Minor textual changes, accommodation of Specifications

12/08 – Revision 2: Minor textual changes, accommodation of Specifications

13/01 – Revision 3: Update Gain of SDD, update Typical Performance Characteristics due to new FET,

update spectral definitions, completion of specification

13/08 – Revision 4: Updated technical drawings chapter 18. Outline Dimensions ,

additional picture concerning thermal budget of low-energy SDDs

13/11 – Revision 5: Updated technical drawings chapter 18. Outline Dimensions

17/10 – Revision 6: Updated technical drawings chapter 18. Outline Dimensions





3. Features

Silicon Drift Detector

energy resolution down to 123eV FWHM at Mn-Kα

excellent peak-to-background

operable at an ambient temperature of up to +80°C with excellent performance

high count rate capability up to 1,000,000 cps

efficient integrated Peltier element

no liquid nitrogen cooling required

radiation hardness during more than 10 years standard count rate exposure

easy to use

active areas from 7 to 100mm² available

4. Applications

XRF

µ-XRF

EDX

EDS

TXRF

XRD

Handheld

5. Functional Block Diagram

Fig. 1: KETEK VITUS SDD Functional Block Diagram

6. General Description

KETEK VITUS Silicon Drift Detectors (SDD) are the state-of-the-art X-ray detectors based on silicon

substrates. Their typical X-ray energy range is between 0.2keV and 30keV. They are used in

applications such as EDX, EDS, XRF, TXRF in bench top as well as in handheld based systems. Due

to their wide operating temperature range they are especially suited for industrial and automotive

applications.



7. Safety

It is strongly recommended to read this user manual carefully and completely before installing or

activating the SDD. Please keep this user manual always with the system for that any operator can get

this important information. In case of resale – even when second hand – or in case of scrapping at the

end of lifetime this manual has to be given along with the system. Please handle the attached

documents “Beryllium Material Data Sheet” and “Statement of contamination…” the same way.

WARNING!

The detector contains a thin, fragile Be window. If this window is damaged, the detector will be destroyed and cannot be repaired.

Be windows damaged due to improper handling are not covered under warranty.

This product uses – a very small amount - of toxic beryllium material at the inner side of the detector foil. Beryllium is preferred as an entrance window coating because i t

provides a light-tight seal and, further, does not introduce spurious peaks in the measured spectrum. In normal operation there is no danger to get in contact with any toxic materials. If the SDD window was destroyed by accident, follow our safety

instructions.

Scrapping at end of lifetime has to be done according to the (local) legal requirements. Make the “Beryllium Material Data Sheet” available to your waste disposal contractor. Do not scrap the SDD to your domestic waste.

Due to the very thin window foil you should take care neither to touch it with fingers nor

to bring other things or materials under test too near to it. Keep away excessive dust particle streams from the SDD window.

Excessive electrostatic discharge might destroy the window. Take care ESD is well bled

off in your application.

Some of the SDD types are evacuated. A damaged entrance window may implode scattering small beryllium particles in the immediate vicinity of the SDD. In this case, rigorously clean the SDD and its surrounding area following all the precautions

mentioned in the “Beryllium Material Safety Data Sheet”.

Always keep the SDD protection cap with the system, even if fixed mounted. It’s necessary for cleaning, service and shipping to be able to protect the beryllium window.

CAUTION!

High voltages need to be applied to the detector for use. To prevent electrical shock, do not touch the detector.

Do not drop or cause mechanical shock to the detector. Components inside the detector

are mechanically fragile and may be damaged if the unit is dropped. Avoid temperature shocks. If the detector is out of allowed temperature range, make

sure to acclimate slowly. Avoid air pressure shocks. Especially in evacuated applications take care to ventilate

slowly. Let the protection cap be mounted at the SDD as long as the system isn’t mounted in its

end application. Your end application has to be designed that way to make unexpected, damaging contact with the SDD window impossible. Make sure your samples under test might never touch the SDD window.

Do not remove the protective cap from the detector until data is to be taken. The detector

window is made from thin beryllium which is extremely brittle and can shatter very easily. Do not have any object come in contact with the window. Do not touch the detector because the oil from the fingers will cause it to oxidize. Use gloves. The window cannot

be repaired. If the window is damaged the detector assembly must be replaced. Be windows damaged due to improper handling will not be covered under warranty. Keep the protective cover nearby at all times and cover the detector when the instrument is not

in use.



Radiation damage to the detector will occur i f it is exposed to a high flux environment.

Synchrotron Radiation Beams should be modified with attenuators before they are allowed to strike the detector or the fluorescence target. Damage to the detector will be

permanent if the flux from an X-Ray Tube, a strong nuclear radiation source, or an accelerator is not attenuated.

No user serviceable parts inside the units. Refer servicing to KETEK GmbH. To prevent electrical shock, do not remove covers.

Keep the device dry and clean!

Warranty

KETEK GmbH warrants to the original purchaser this instrument to be free from defects in materials

and workmanship for a period of one year from shipment. KETEK GmbH will, without charge, repair or

replace (at its option) a defective instrument upon return to the factory. This warranty does not apply in

the event of misuse or abuse of the instrument or unauthorized alterations or repair. KETEK GmbH

shall not be liable for any consequential damages, including without limitation, damages resulting from

the loss of use due to failure of this instrument. All products returned under the warranty must be

shipped prepaid to the factory with documentation describing the problem and the circumstances

under which it was observed. Additionally the statement of contamination must be filled out completely

and returned with the product. KETEK must be notified prior to return shipment. The instrument will be

evaluated, repaired or replaced, and promptly returned if the warranty claims are substantiated. A

nominal fee will be charged for unsubstantiated claims. Please include the model and serial number i n

all correspondence with KETEK.

Care Instructions

Do not clean the SDD under any circumstances. Do not use any alcoholic, acid or rubbing cleaning

agents.

8. General Restrictions and Recommendations

- do not use detector without heat sink connection. Overheating will destroy the module

- do not solder the pins or any other part of the detector module

- avoid touching the detector module

- use gloves to avoid corrosion

- avoid touching the entrance window of the detector module. It contains hazardous materials



9. Specifications

Parameter Conditions/Comments Min Typ Max Tolerance Unit

VOLTAGES measured before filtering

R1 -25 -20 -5 ±1 V

RX -160 -130 -80 ±5 V

BACK -100 -65 -35 ±2 V

FET-Substrate/Bulk -7 -4 -2 ±1 V

Drain 1 3 4 ±0.1 V

CURRENTS

R1 = RX 5 10 20 ±5 µA

BACK* at maximum cooling 1 2 ±0.1 nA

Drain 2 3 4 ±0.1 mA

Temp.-Sensor 0.1 1 5 ±0.1 µA

PELTIER (TEC) -35°C operating temp @ 20°C heat sink temp.

Voltage H7 / H20 / H30 / H50 1.6 1.7 1.8 ±0.1 V

Current H7 / H20 / H30 / H50 250 300 350 ±10 mA

maximum cooling @ 20°C heat sink temp.

Voltage H7 / H20 / H30 / H50 3.0 3.3 3.6 ±0.1 V

Current H7 / H20 / H30 / H50 600 650 700 ±10 mA

Gain 0.9 ±30% mV/keV * Back voltage absolute value should not exceed one half of the RX voltage absolute value by more than 10V

These specifications refer to the whole VITUS SDD class. Please refer to the individual SDD datasheet for detailed information.

Type Active Area Window

Cooling

Performance

Guaranteed

FWHM

Guaranteed

P/B

Typ. FWHM @

100kcps

Guaranteed

FWHM

Guaranteed

P/B

Typ. FWHM @

100kcps[mm²] Max T @ 30°C heat sink @ 8µs PT [eV] dead time <50% [eV] @ 8µs PT [eV] dead time <50% [eV]

H7 7 8 µm Be 75 ≤ 129 > 15,000 ≤ 139 ≤ 139 > 6,000 ≤ 144

H20 20 8 µm Be 75 ≤ 129 > 15,000 ≤ 139 ≤ 139 > 6,000 ≤ 144

H30 30 8 µm Be 75 ≤ 129 > 15,000 ≤ 139 ≤ 139 > 6,000 ≤ 144

H50 50 12.5 µm Be 75 ≤ 129 > 15,000 ≤ 139 ≤ 139 > 6,000 ≤ 144

H80 80 25 µm Be 75 ≤ 136 > 10,000 ≤ 144 ≤ 160 > 5,000 ≤ 180

R100 92 25 µm Be 75 ≤ 136 > 400 ≤ 144 ≤ 160 > 400 ≤ 180

Type Active Area Window

Cooling

Performance

Guaranteed

FWHM

Guaranteed

P/B

Typ. FWHM @

100kcps

Guaranteed

FWHM

Guaranteed

P/B

Typ. FWHM @

100kcps[mm²] Max T @ 20°C heat sink @ 8µs PT [eV] dead time <50% [eV] @ 8µs PT [eV] dead time <50% [eV]

H7LE 7

AP3.3

low-energy

window

55 ≤ 133 > 15,000 ≤ 139 ≤ 139 > 6,000 ≤ 144

H15LE 15

AP3.3

low-energy

window

55 ≤ 136 > 15,000 ≤ 139 ≤ 144 > 6,000 ≤ 144

Premium Class Standard Class

VITUS Silicon Drift Detectors

VITUS Silicon Drift Detectors with low-energy window

Premium Class Standard Class



10. Absolute Maximum Ratings

Parameter Rating

VOLTAGES

R1 ≥ -30V

RX ≥ -180V

BACK* ≥ -100V

FET-Substrate/Bulk ≥ -15V

Peltier H7/H20/H30/H50 ≤ 3.6V

Peltier H80 ≤ 4.5V

Peltier H7LE/H15LE/H20LE ≤ 4V

CURRENTS

RX ≤ 1mA

Drain ≤ 10mA

Temp.-Sensor ≤ 50µA

Peltier H7/H20/H30/H50 ≤ 700mA

Peltier H80 ≤ 1000mA

Peltier H7LE/H15LE/H20LE ≤ 900mA

Radiation Hardness @17keV ≤ 1012 Photons

Torque ≤ 0.8Nm

Stresses beyond those listed under Absolute

Maximum Ratings may cause permanent

damage to the device. This is a stress rating

only; functional operation of the device at these

or any other conditions above those indicated

in the applications and operations section of

this specification is not implied. Exposure to

absolute maximum rating conditions for

extended periods may affect device reliability.

* Back voltage absolute value should not exceed one half of the RX voltage absolute value by more than 10V



11. Ambient Conditions

Parameter Min Max Unit Conditions

OPERATING

Temperature 0 60 °C

Humidity 10 80 % RH non condensing

Pressure 0 1.1 atm

Pressure Change 100 mbar/s

STORAGE

Temperature 0 60 °C

Humidity 10 90 % RH non condensing

12. ESD Caution

ESD (Electrostatic Discharge) sensitive device.

Charged devices and circuit boards can discharge without detection. Although this product features patented or proprietary

protection circuitry, damage may occur on devices subjected to high energy ESD. Therefore, proper ESD precautions should be taken to avoid performance degradation or loss of functionality.

13. Pin Configuration and Functional Descriptions

VITUS H7, H20, H30, H50 VITUS H80, R100

Pin No. Description Mnemonic Pin No. Description Mnemonic

1 Temp Sensor - /GND TD- /GND 1 Peltier - P-

2 Temp Sensor + TD+ 2 Ring X RX

3 Ring 1 R1 3 Feedback FB

4 Back BK 4 Peltier + P+

5 Reset RES 5 Drain FFD

6 FET-Substrate / Bulk SUB / BULK 6 Source FFS

7 Source FFS 7 Reset RES

8 Drain FFD 8 FET-Substrate / Bulk SUB / BULK

9 Feedback FB 9 Back BK

10 Peltier + P+ 10 Ring 1 R1

11 Ring X RX 11 Temp Sensor + TD+

12 Peltier - P- 12 Temp Sensor - /GND TD- /GND



14. Typical Performance Characteristics

Fig. 2: Typical KETEK VITUS Silicon Drift Detector Spectrum of H7 active area type SDD with an Fe-55 source,

taken with a KETEK preamplifier and a digital pulse processor.

Fig. 3: Definition of Peak-to-Background (P/B) and Peak-to-Tail (P/T) of a typical spectrum

taken with a KETEK preamplifier and a digital pulse processor.



Fig. 4: Typical transmission of KETEK Silicon Drift Detectors with different Beryllium entrance window thickness

Fig. 5: Typical transmission of KETEK Silicon Drift Detectors with low energy AP3.3 entrance window

Fig. 6: Typical absorption efficiency of KETEK Silicon Drift Detectors with a thickness of 450µm and 8µm Beryllium window

500 1000 1500 2000 2500 3000

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

Tra

nsm

issi

on

Photon energy (eV)

8 µm

12.5 µm

25 µm



20 25 30 35 40 45 50 55 60 65 70 75 80

-40

-35

-30

-25

-20

-15

-10

-5

0

5

10

SD

D C

hip

Te

mp

era

ture

[°C

]

Heat Sink Temperature [°C]

e.g. stable 0°C chip temperature

up to +70°C heat sink temperature

e.g. stable -10°C chip temperature

up to +55°C heat sink temperature

e.g. stable -20°C chip temperature

up to +40°C heat sink temp.

Fig. 7: Typical control range of Silicon Drift Detector chip temperature at different ambient temperatures for vacuum

encapsulated BE-window type SDDs and low-energy type SDDs

Fig. 8: Typical calculated energy resolutions of Silicon Drift Detectors for low energies

Fig. 9: Typical Input to Output Count Rate Ratio (Throughput) for different Peaking Times

taken with a KETEK VITUS H30 SDD and an XIA Mercury Digital Pulse Processor



H7

H20

H30

H50

H80

H7-LE

H15-LE

Fig. 10: Typical KETEK VITUS Silicon Drift Detector Spectrum with an Fe-55 source, taken with an KETEK preamplifier and an XIA Mercury digital pulse processor for the different VITUS active areas.



H7

H15 / H20

H30

H50

H80

Fig. 11: Typical energy resolution for different chip operating temperatures dependent on the Peaking Time for different SDD sizes.



H7

H15 / H20

H30

H50

H80

Fig. 12: Typical energy resolution for different input count rates dependent on the Peaking Time for different SDD sizes.



15. Theory of Operation

The silicon bulk of the Silicon Drift Detector (SDD) has to be depleted completely to make the sensor

sensitive for incoming photons. By applying a negative voltage to the back contact of the SDD, the

detector bulk is completely depleted. An incoming photon will generate a number of electrons and

holes dependent on its energy. The holes drift to the back side of the detector formed by the large

area back contact whereas the electrons drift to the anode where the accumulated charge can be

measured or read out. The drift field for the electrons is applied by a ring structure on one side of the

SDD with a negative voltage at the outer ring (Ring X) and a voltage close to 0V at the innermost ring

(Ring 1).

Fig. 13: Silicon Drift Detector potential diagram

The anode is connected to: a) the gate of the first field effect transistor (FET), b) the feedback

capacitance (CFB) and c) the cathode of the reset diode (DRES). The combination of a) and b), the FET

and the feedback capacitance, respectively, forms the first part of a charge sensitive amplifier, used to

read out the accumulated electrical charge. The combination forms a transimpedance (current to

voltage) and an integrator when connected to the subsequent stages of the pre-amplifier. Therefore

the source of the FET has to be connected to ground and the drain voltage and current need to be set

appropriately (typically 3V and 3mA). The operating point of the FET is optimized by setting its bulk or

substrate voltage.

Fig. 14: Silicon Drift Detector schematic

GND UOR UIR

UBACK

Homogeneous thin entrance window

-V

Driftfield Anode



The FET is operated in a common source configuration. The leakage current sensed at the FET gate

causes a ramp signal at the output of the pre-amplifier. The slope of the ramp signal, and thus its

frequency, is dependant on the operating temperature. The incoming photons generate short current

pulses, with a certain rise time (dependant on the location of interaction of the x -ray with the SDD

chip), and a certain duration and amplitude (dependent on the energy of the incoming photon). In turn,

these short pulses generate steps superimposed on the pre-amplifier’s ramped output signal. The

height of a step contains the information necessary to determine the energy of the interacting photon.

Fig. 15: Typical KETEK Preamplifier Output Signal including Preamplifier Reset Pulse Output

using a KETEK VITUS SDD irradiated with an Fe-55 Source at -35°C Operating Temperature

Fig. 16: Zoom of Figure 15, typical KETEK Preamplifier Output Signal including Preamplifier Reset Pulse Output

using a KETEK VITUS SDD irradiated with an Fe-55 Source at -35°C Operating Temperature showing step like pulses

-1,5

-1

-0,5

0

0,5

1

1,5

0 5 10 15 20

Time [ms]

Am

pli

tud

e [

V]

Preamp Out

Reset Out

-0,16

-0,12

-0,08

-0,04

0

0,04

0 20 40 60 80 100 120

Time [µs]

Am

pli

tud

e [

V]

PreampOut



16. Application and Operation Information

For (optimal) operation, SDDs require the application of several voltages and integration with a charge

sensitive amplifier and other pulse forming electronics (either analog or digital). Typically, a high

voltage DC power supply feeds the drift ring voltages; a high current, linearly regulated, low voltage

power supply feeds the Peltier element; and a bipolar, linearly regulated power supply feeds the

charge sensitive amplifier and pulse forming electronics.

The drift ring voltages can be generated from a filtered high voltage rail, by using several voltage

dividers. Each detector may have individual ring currents. Thus potentiometers should be used for

voltage adjustments as the voltage drop at the voltage dividers depends on the ring currents.

Fig. 17: KETEK Silicon Drift Detector connected to typical preamplifier board – block diagram

The Peltier power supply should be regulated with a PI/PID loop to keep the operating temperature of

the SDD chip stable. Therefore it is necessary to read out the temperature sensor of the SDD.

16.1. Wiring

The SDD should be placed as close as possible to the preamplifier. It is recommended to shield at

least the preamplifier connections. It is strongly recommended using a single point ground. Please

note that also the housing of the SDD should be connected to ground.

16.2. Mechanical Connection

WARNING: Do not operate the detector without proper heat sink connection.

Overheating of the detector will destroy the module.

It is strongly recommended to install the detector connected to a proper heat sink. Dimensioning the

heat sink is dependant on ambient temperature, air ventilation, operating temperature of the SDD,

surface area and its condition. The guaranteed operating temperature is always related to the heat

sink temperature. Therefore the minimum operating temperature can vary and is directly dependant on

the quality of the heat sink interconnection.



16.3. Read out Circuit for Temperature Sensor

a) Temperature Diode:

Using a diode as temperature sensor leads to a linear relationship between the measured voltage and

sensor temperature. The line’s slope depends on the diode bias current . For the recommended 1µA,

the slope is 2.35mV/K. It is recommended to apply a constant current.

b) Thermistor (NTC resistor):

In case of the thermistor the temperature function is given by the following equation:

3843 )ln(10775468.8)ln(10341077.210129241.11

RRT

The function is shown in the following plot. At 25°C the resistance is 10kΩ.

Fig. 18: Temperature function of a thermistor as SDD temperature sensor

To read out the temperature sensor, the following schematic is recommended. Although a diode (D1)

is shown in the schematic, it may be replaced with a thermistor (say, Rt); the equations given below

apply, if D1 is replaced with Rt. R4 limits the maximum current through the temperature sensor and

should be set as follows:

)1(

14

DI

V

I

UR

For example: The voltage V1 is +5V and the current I(D1) should be 1µA. This leads to R4=5MΩ.

R1 and R2 form a voltage divider representing the offset voltage. They can be used to set the circuit’s

signal swing, given the operational demands on the SDD, e.g. i f an ADC is used to digitize the voltage,

tuning R1 and R2 would ensure the desired temperature range corresponds to voltage values in the

ADC’s range.

R1, R2 and R3 determine the gain of the circuit. The gain can be calculated as follows:

)21(

31

RR

RA

-100 -50 0 50 100 150

100

1000

10000

100000

1000000

1E7

Re

sis

tan

ce

[O

hm

]

Temperature (°C)



Fig. 19: Typical Read out Circuit for temperature sensors with linearization, offset correction and gain.

16.4. Operating Voltages

Several voltages are needed for operating the detector (exact values are given in each detector data

sheet), for example:

1. Ring 1 = approx. -20V

2. Ring X = approx. -130V

3. Back = approx. -65V

The detector voltages should be filtered using the following combinations of resistors and capacitors

providing low pass filters:

1. Ring 1: RR1 = 15kΩ, CR1 = 220nF

2. Ring X: RRX = 500kΩ, CRX = 47nF/250V

3. Back: RBack = 1MΩ, CBack = 47nF/250V

Fig. 20: Operating voltages filtering block diagram



Before switching on the system, the output-signal of the preamplifier and the shaped signal should be

connected to an oscilloscope.

The preamplifier operating voltage must be switched on first.

The detector voltages should be switched on in the following order:

R1 – RX – Back

The voltages to be applied must be set according to the detector datasheet . Typical currents flowing

are several μA through Ring 1 and Ring X (voltage divider) and approx. 1nA for the back contact if the

back voltage is applied. R1 and RX currents should be equal!

After switching on the detector voltages the signal of the preamplifier should show a ramp. The ramp

period depends on the chip temperature. At -35°C the ramp period should be in the range of several

microseconds.

16.5. Preamplifier Design

For the design of the preamplifier it is recommended to use the FET in the common source

configuration. Therefore the source of the FET can be connected directly to signal ground. The drain

drives the signal. The substrate or bulk should be adjusted to the value given in the datasheet of each

single SDD. Also a low pass filter should be used to suppress any noise. Typical values are:

Substrate/Bulk: RSUB = 10kΩ, CSUB = 4.7µF/16V Tantalum, low ESR

The drain can be driven by a simple current source formed by a resistor. Additional low pass filtering is

mandatory. Tantalum capacitor with low ESR of at least 100µF should be chosen.

The Drain and Feedback lines should be well separated to avoid any ringing or crosstalk. It is

recommended to shield at least one of the above lines.

The Reset circuit should include a current limiter. This will protect the sensitive reset diode mechanism

inside the SDD. It is recommended to use an in-line resistor of at least 2kΩ.

Fig. 21: Preamplifier connection block diagram



16.6. Peltier Characteristics

The KETEK Silicon Drift Detectors are provided in three different performance grades, based on the

package’s internal atmosphere and size: evacuated TO-8 packages (H7, H20, H30, and H50);

evacuated non-TO-8 packages for larger devices (H80, R100); and, low-energy, nitrogen filled TO-8

packages (H7-LE, H15-LE). The three types have different cooling capabilities because of the

different internal atmosphere (vacuum or nitrogen) and different sizes.

Fig. 22: Typical power consumption of the three different KETEK VITUS SDDs

It is strongly recommended to limit the current as mentioned in chapter “10. Absolute Maximum

Ratings”. Stresses above those listed under “Absolute Maximum Ratings” may cause permanent

damage to the device. Functional operation of the device at these or any other conditions above those

indicated in the applications and operations section of this specification is not implied. Exposure to

absolute maximum rating conditions for extended periods may affect device reliability.

Please note that the behaviour of the Peltiers can vary with changed ambient temperatures. The

efficiency of the Peltier elements is increasing approximately by 0.5K for each Kelvin of increasing

ambient temperature. Additionally the step response factor will change which will influence the

parameters of the control loop for the regulation of the operating temperature.

0

1

2

3

4

-60 -50 -40 -30 -20 -10 0 10 20

Temperature [°C]

Po

we

r [W

]

H7-LE

H80

H7



Fig. 23: Typical H7 step response functions for different Peltier currents

using a diode as temperature sensor with 1µA operating current and 10V compliance voltage.

Fig. 24: Typical H80 step response functions for different Peltier currents


Fig. 25: Typical H7-LE step response functions for different Peltier currents


-60

-50

-40

-30

-20

-10

0

10

20

0 50 100 150 200 250 300 350 400

Time [s]

Tem

pera

ture

[°C

]

100mA

200mA

300mA

400mA

500mA

700mA

-60

-50

-40

-30

-20

-10

0

10

20

0 50 100 150 200 250 300 350 400

Time [s]

Te

mp

era

ture

[°C

]

100mA

200mA

300mA

400mA

500mA

600mA

700mA

800mA

1000mA

900mA

-60

-40

-20

0

20

0 50 100 150 200 250 300 350 400

Time [s]

Te

mp

era

ture

[°C

]

100mA

200mA

300mA

400mA

500mA

600mA

700mA

900mA



17. Collimator

The KETEK Multilayer Collimator consists of a Tantalum (Ta) foil covered with stacked layers of

Chromium (Cr), Titanium (Ti) and Aluminium (Al). The purity of the layers is ≥99%.

All collimators are mounted on-chip.

Fig. 26: KETEK multi-layer collimator

Optionally, KETEK offers an external outer clip-on collimator VPROTECT. Depending on the

application, the geometry of the x-ray beam can differ. To avoid any foreign absorption or fluorescence

the additional collimator can optimize the beam geometry.

Fig. 27: KETEK additional external clip-on collimator



18. Outline Dimensions

H7LE H18LE

H7 H20 H30

H50 H80 H150

Fig. 28: Outline dimensions of the different KETEK VITUS Silicon Drift Detector types

Ø



19. Footprint

For H7, H20, H30, H50 SDDs: (Bottom View), M4x6 Screw

Mating connectors:

- Type Tyco Electronics/AMP 6-5330808-5

For H80 and H150 SDDs: (Bottom View), M6x8 Screw

Mating connectors:





20. Ordering Guide

V 5 F 2 O - -

Pro

duct

VIT

US

Chip

thic

kness

450µ

m

FE

T

Peltie

r

Tem

p.

Sensor

Chip

entr

ance

win

dow

Active a

rea

Colli

mato

r

mate

rial

Cap

Win

dow

Encapsula

tion

Example:

V5F2T0-H30-ML8BEV: VITUS 450µm SDD Chip with low capacitance FET and a Thermistor as

temperature sensor, active area of 30mm² with high peak-to-background ratio, multilayer collimator in

a bevelled cap with a Be window sealed under vacuum.

21. Optional

Optional available are different KETEK products in combination with the VITUS Silicon Drift Detector:

- KETEK Preamplifier: High performance stand-alone preamplifier for SDD applications

- KETEK VICO: VITUS Components, -PA: Preamplifier, -TC: TEC/Peltier Controller, -HV: High

Voltage Power Supply, -DP: Digital Pulse Processor, -EV: Evaluation Board

- KETEK VIAMP: VITUS SDD in combination with preamplifier

- KETEK AXAS: Analytical X-ray Acquisition System

- KETEK VPROTECT: external collimator

For detailed information please contact KETEK Sales and Marketing Office.



22. Contact

KETEK Headquarter Sales Office

KETEK GmbH

Hofer Str. 3

81737 München

Email [email protected]

Phone +49 (0) 89 673467 75

Fax +49 (0) 89 673467 77

www.ketek.net

mailto:[email protected]

http://www.ketek.net/

Documents

VITUS Silicon Drift Detectors - KETEK GmbH€¦ · · 2017-10-19KETEK VITUS Silicon Drift Detectors (SDD) are the state-of-the-art X-ray detectors based on silicon ... damaging