Development of two important Finnish innovations: Humicap and
ALD Tuomo Suntola FROM MATERIALS PHYSICS TO NANOSCALE DEVICES 50
YEARS OF FINNISH RESEARCH IN SEMICONDUCTOR TECHNOLOGY Slide 2
Capacitive humidity sensor - Humicap Pre-study by Tapio Wiik:
Capacitive humidity sensors had been demonstrated with porous Al 2
O 3 thin films and with polymer foil; Nylon foil humidity sensor
was patented by Honeywell. The operational principle: Absorption of
water vapor in a dielectric material result in an increase of the
dielectric constant and the capacitance measured. Request to VTT
Semiconductor laboratory by Vaisala Oy in 1971: Development of a
micro-sensor alternative for humidity measuring at weather stations
and in radiosondes. Tuomo Suntola started the development with Anja
Savolainen as laboratorian in December 1971. The polymer line was
selected: Instead of using a self supporting foil, the polymer
material was dissolved in a solvent and a polymer film was formed
on a glass substrate using a spinner (like used for photoresist in
the lab) or by drawing up the substrate uniformly from the polymer
solution. Jorma Antson joined the team in late summer 1972, the
development was completed by the end of 1973. Slide 3 Capacitive
humidity sensor - Humicap + Nylon material was advantageous for
having a low hysteresis. -The temperature and frequency dependence
of the capacitance was substantial. A specific polymer material
with linear response and practically zero temperature dependence
was found. 0 50 100 Capacitance Relative humidity (%) 0 50 100
Capacitance Relative humidity (%) With all polymers tested, the
hysteresis was substantially lower in thin film structures than it
was in self-supported foil structures. Slide 4 Capacitive humidity
sensor - Humicap The thin film structure comprised -Very fast
response -Large temperature range -Low temperature dependence
-Suitable for mass production A prototype sensor made in 1973. The
sensor was fully functional when photographed in 2014. Slide 5
Capacitive humidity sensor - Humicap
http://www.vaisala.com/en/corporate/cases/Pages/humicapcelebratesits40years.aspx
As the worlds first thin-film capacitive humidity sensor, the
HUMICAP was a radical innovation that completely changed the way
humidity is measured. The new ground- breaking technology had no
moving parts, and it was amazingly small due to the advanced use of
thin-film technology. Today, Vaisala is the market leader in
relative humidity measurements, and thin-film capacitive humidity
sensors have developed from one companys innovation into a global
industry standard. Slide 6 MEMS research activity, VTT From
humidity sensor to EL-panels and ALD Request for proposals for new
products Instrumentarium Oy Search for new challenges Late 1973
Humicap humidity sensor to Vaisala Oy, 1973 1.1.1974 Research unit
Vaisala: Investment in IC-technology Pressure sensors Acceleration
sensors VTI technologies 1991 Murata Electronics 2012 Okmetic Slide
7 The proposal ? ? ? ? ? ? ? ? I am still confused lets go ahead
Lets develop an electroluminescent flat panel display EL nobody has
done it yet but at a higher level Thin film technology, sensors,
output devices Market research: -medical instrumentation, key
components Lecture given on future displays at INSKO Request for
proposals for new products Slide 8 The problem and the solution
State of the art: -High performance demonstrated -Major problems
with stability due to the high operational voltage Novel thin film
processing technique is needed Well order material requires well
ordered processing conditions How about sequential buildup of
compounds? May - June 1974 Well controlled electronic properties
require well ordered material Slide 9 The 1 st ALE process for ZnS,
September 1974 12 th Baltic ALD, Helsinki 2014 12.05.2014 9 Idea of
sequential buildup of compounds, June 1974 Construction of a test
equipment 10 torr 360 C 4x10 torr 3x10 torr 2x10 torr 2 c/s Zn S
320 C 100 C 0.4 mm 0.6 0.2 0 0 10 20 minutes Hexagonal ZnS:
monolayer 3.13 n=2.36 1/3 x monolayer Optical thickness monitoring
Slide 10 Need, ideas, solution, demonstration, basic patents
197019801990200020102020 Early ALD reactors EL demos Slide 11 Need,
ideas, solution, demonstration, basic patents
197019801990200020102020 Early ALD reactors EL demos Meeting the EL
target Pilot production of EL panels Commercial production of EL
panels, Lohja Planar Beneq Elcoteq Picopack Slide 12 Need, ideas,
solution, demonstration, basic patents Product prototypes, reactors
for EL production Commercial production of EL panels, Lohja Planar
Beneq 197019801990200020102020 Research for better understanding of
ALD chemistry Microchemistry Ltd 40 years of ALD reactors
commercial reactors Slide 13 2004 Picosun Oy 2005 Beneq Oy Need,
ideas, solution, demonstration, basic patents Product prototypes,
reactors for EL production Commercial production of EL panels,
Lohja Planar Beneq 197019801990200020102020 Research for better
understanding of ALD chemistry Microchemistry Ltd 1999 ASM
Microchemistry, commercial reactors & processes 40 years of ALD
reactors commercial reactors Slide 14 Helsinki University of
Technology University of Joensuu 2004 Picosun Oy 2005 Beneq Oy
Need, ideas, solution, demonstration, basic patents Product
prototypes, reactors for EL production Commercial production of EL
panels, Lohja Planar Beneq 197019801990200020102020 Research for
better understanding of ALD chemistry Microchemistry Ltd,
commercial reactors 1999 ASM Microchemistry, commercial reactors
& processes From ideas to global industry 1984 16 th Conference
on Solid State Devices and Materials Kobe, Japan ACSI conferences
ALE-4 Linz 1996 The European SEMI Award 2004 was handed to Tuomo
Suntola at the Munich Electronics Show 2004 by Stanley Myers, the
President & CEO of SEMI (USA) Honoring the Pioneer in Atomic
Layer Deposition Techniques... that paved the way for the
development of nanoscale semiconductor devices". Explosive increase
in ALD activity - research & industrial Centre of Excellence
Slide 15 A Short History of Atomic Layer Deposition: Tuomo Suntolas
Atomic Layer Epitaxy By Dr. Riikka L. Puurunen, VTT Technical
Research Centre of Finland, Espoo, Finland riikka.puurunen @vtt.fi
Slide 16 Thank you for your attention! FROM MATERIALS PHYSICS TO
NANOSCALE DEVICES 50 YEARS OF FINNISH RESEARCH IN SEMICONDUCTOR
TECHNOLOGY
