Budapest University of Technology & Economy Department of Electron Devices.

http://www.eet.bme.hu

Budapest University of Technology & Economy

Department of Electron Devices

The Department of Electron Devices

• The only university department in Hungary dealing with all aspects of microelectronics.

• Highly acknowledged European research center

The Department of Electron Devices

Expertise in • device physics,• microelectronics CAD tools

– esp. thermal simulation & circuit simulation, • IC & MEMS design,• gas sensors,• thermal issues,• multimedia, internet applications

Education (continued)

Special subjects:– Microelectronics CAD (basic concepts in digital

VLSI design, CAD systems, basics of layout level & analog design)

– ASIC & FPGA Laboratory (design of an MSI circuit)

– High level synthesis (VHDL, hardware synthesis methods)

– VLSI Laboratory (introduction to Cadence Opus, design of a standard cell in Opus)

Education (continued)

Special subjects:

– Monolyth technology (+ processing practice in the semiconductor laboratory)

– Integrated microsystems– Testing laboratory (for ICs, semiconductor

materials, MEMS packages and structures,)– Course laboratories (topics are selected from all

above issues)

Research• European projects:

BARMINT, THERMINIC, HIPERLOGIC, TALENT, DETERMIN, PROFIT, REASON, PATENT

• thermal measurements (IR, LC, transient)

• thermal simulation

• thermal testing

• electro-thermal simulation

• compact dynamic thermal modeling

• MEMS design, simulation and characterisation

Research facilities

Laboratories:

• Thermal laboratories• VLSI CAD Laboratory• Semiconductor laboratory• FPGA Laboratory

Research facilities

CAD Laboratory Facilities (hardware)

– SUN Enterprise Ultra server, WNT server, – 10 SUN workstations – 100/10 Mbps LAN, 4 network printers– 20 Linux workstations– Tektronix LV500 IC tester

Facilities

• Installed software tools:– Cadence Opus

• AMS 0.8

• ST 0.25

• Mietec 2.4

• CMP MEMS Engineering Kit

– Atmel-ES2 SOLO 1400 (for education only)

– HSpice, Spectre

– THERMAN & SUNRED tools of MicReD

Facilities Using Cadence Opus

in the SUN Laboratory

FacilitiesTektronix LV500 IC tester

Facilities - Thermal laboratory

LC based thermal imaging system

Aga 782 IR camera with PC interface

Facilities - Thermal laboratory

The department’s thermal transient tester

Commercialized version of the transient tester

Facilities - semiconductor laboratory

Scanning electron-microscope with PC interface

Facilities - semiconductor laboratory

Diffusion furnace

Sputtering and evaporation are also available

Facilities - semiconductor laboratory

Spreading resistance meter

….without contacts on the surface

Facilities - semiconductor laboratory

Some research results Design of CMOS temperature sensors

Generic designs, almost process independent behavior

Frequency output version

Some research resultsDesign of thermal test dies

Following this experiences, a more sophisticated chip has been designed together with the MicReD company...

5x5 dissipator / sensor cells

Tester-on-the-die: dissipator + sensor + boundary scan - first realization

Some research resultsDesign of thermal test dies

Our recent design: 81 individually programmable dissipator / temperature cells with boundary scan interface: improved implementation of the two older designs, 6x6 mm2, 8 W

Some former research resultsElectro-thermal simulation

Experimental system implemented in Cadence Opus on top of the ECPD07 design kit of Atmel-ES2

Some former research resultsLiquid crystal thermal imaging of ICs

Some research resultsSophisticated post-

processing of IR images

Thermal transient recording using the IR camera

Some recent research results Thermal transient testing of IC packages

Identification of properties of the chip-to-ambient heat-conduction path based on thermal transient measurements

0

5

10

15

20

25

30

35

1e-06 1e-05 0.0001 0.001 0.01 0.1 1 10 100

Tem

pera

ture

ris

e [

Cel

s]

Time [s]

miTTT: RECORD=B1DMon Oct 23 22:23:39 2000

"B01d.MR1""B02d.mr1""B03d.mr1""B04d.mr1""B05d.mr1""B06d.mr1"

0.01

0.1

1

10

100

1000

0 1 2 3 4 5

K

[W2s

/K2]

Rth [K/W]

miTTT: differential structure functionMon Oct 23 23:20:33 2000

"C08D.stf""C02D.stf""C05D.stf""C17D.stf"

The so called structure functions provide the required information

Detecting die attach and soldering failures The differential structure function of the reference device

1: the transistor case

2: the copper island of the mounting plate

3: the total mounting plate

4: the cold plate

Rth of the soldering

Rth of the plastic coating

Detecting die attach and soldering failures Comparison of the differential structure functions of C02 and C08

Rth between 2 and 3 increased

The soldering error can be noticed even visually

3 3

Some recent research results Thermal transient testing of IC packages

•Identification of properties of the chip-to-ambient heat-conduction path based on thermal transient measurements

•Identification of the partial thermal resistances in the heat flow path enabling detection of die attach and soldering failures

•Calculation of effective thermal conductivity and emissivity values from the measured results, etc

Some recent research results Compact thermal model generation

A package

The generated BCI

(Boundary condition independent) compact model

Some recent research results BCI Compact thermal model generation

The transient results (FS=field solver, CM=compact model)

Some recent research results Investigation of surface potentials on different materials

 Vibrating capacitor with transparent reference electrode

Some recent research results Gas sensing: the adsorption induced shifts in work function

differences at 460-360K (Pd-Ag-Au-Pt-V-Pt-SnO2) (Kelvin method)

Pd Ag Au Pt V Pt SnO2

C

30mm

25m

m

1% H2 -air mixture NH4OH vapour (NH3) CHCl3 vapour C2H5OH vapour

460K

360K

Further research in progress

• Enabling board level simulators to accept packages with their compact thermal models

• Design for testability of MEMS structures• Thermal transient examination of power circuits• Development of a fast and user friendly electro-static

solver• Development of a methodology to detect die attach

failures in packages with transient thermal testing• Research in low power circuit design• Research in surface potential measurement• Development of gas sensors • Characterisation of solar cells by different methods, etc