bluuebunny/crossref_metadata_2025 huggingface dataset:
Tantalum Thin Film Applications – A New Approach for Capacitors
Authors: Perinati A.
Published: June 2007

Tantalum‐based materials and process developments have increased the use of tantalum films, combined with silicon
integrated circuits, to form hybrid integrated circuits which can meet the demands of telecommunication systems.
This paper, after a historical review, describes the status of tantalum thin film technology used at Telettra in the
implementation of circuits for telecommunication equipment. In particular, this paper focusses on the efforts
devoted to the improvement of the β‐Ta capacitor process in terms of yield and reliability for RC active filter
realization. The results of a new Ta2 O5 –β Ta deposition process, where a Ta2 O5 layer is first formed by d.c.
reactive sputtering in oxygen in the same vacuum batch where the β‐Ta film is sequentially formed, are given.
Biotelemetry and Radiotracking of Wild Birds: Portable Device Using Solar Cells Power Supply
Authors: Aucouturier J. L. , Chaillou A. , Nicolas G. , Canivenc R. , Govaerts R. , Mertens R. , Lauwers F. , Van Overstraeten R. J. , Marques M.
Published: June 2007

A thick film hybrid transmitter for the radio tracking of wild animals is described. Weight considerations are of
prime importance for such transmitters and the system discussed uses thick film hybrid technology, together with a
solar cell power supply charging Cd–Ni batteries.

To reduce power consumption a pulsed system is used; the transmitter operating frequency is in the 72 MHz
band.
Development and Production of Hybrid Circuits for Microwave Radio Links
Authors: Malmin Per Chr.
Published: June 2007

During the last few years, the use of hybrid integrated circuits in microwave radio links has increased significantly.
This paper reports on a range of microwave hybrid circuits now in production at our plant. These include transistor
high power amplifiers, low noise mixers and various other circuits. The hybrid technology has proven to be cost
competitive with the more conventional waveguide and coaxial technologies, and gives quite a few other advantages
as well. Among these, the standardization of packages and modules is discussed in some detail. The trend is now to
use the hybrid technology in VHF circuits as well. This opens up the possibility of integrating related functions in
one package. The production cost in this case must be related to printed circuit boards, and it remains to be seen if
there is anything to gain in this respect. However the reduction of the size of modules and the time for circuit
alignment will certainly give an improvement in the overall system cost. In order to reduce the cost of microwave
hybrid circuits, thick film technology is currently being investigated for use up to 15 GHz. There is probably no
specific upper frequency for thick film circuits, but the possibility of using conventional thick film technology
depends on the actual circuits under consideration. Preliminary results of this work are reported, together with a
cost comparison between thick film and thin film microwave hybrid circuits.
A High Voltage, High Performance Thick Film Resistor System
Authors: Stein Sidney J. , Huang Cornelius , Gelb Allan S.
Published: June 2007

This paper describes a new series of thick film resistors based on a ruthenium‐compound semiconducting phase,
dispersed in a carefully selected and compatible glassy matrix. Analysis of the electrical properties of these resistors
indicates that the conducting networks present in the structure include ohmic, non‐ohmic and insulating barriers.

Experimental results on the resistors are discussed in terms of resistivity and TCR vs. firing parameters. The effect
of termination materials and resistor geometry, voltage coefficient of resistance, power loading and high voltage
properties are also discussed.
An X‐Ray Technique for Evaluating the Structure of Films for Device Applications
Authors: Clarke R. N. , Court Ian N.
Published: June 2007

Thin films are composed of many crystallites. Where such films are used in the construction of devices it is
frequently necessary to grow them with a preferred orientation. A quick, non destructive method to measure the
degree of orientation could provide a useful guide to device performance. We have investigated a technique to
obtain this information using the Philips P.W. 1050/25 diffractometer. The method depends on being able to tilt
the film out of the diffracting plane of the diffractometer and can be used for films in which all crystallites are
orientated to better than ±25°, of the preferred direction. This limit is generally acceptable since greater misorientation
will normally produce a poor device. The axial beam divergence of the diffractometer is shown to limit
the accuracy of the technique for very highly orientated films. Experimental Verification of the method is described.
Size and Grain‐Boundary Effects in the Electrical Conductivity of Thin Monocrystalline Films
Authors: Tellier C. R.
Published: June 2007

By assuming that the scattering processes from other sources than grain‐boundaries can be described by a single
relaxation time τ∗ and then by solving a Boltzmann equation in which grain‐boundary scattering is accounted for,
we have obtained an analytical expression for the thin monocrystalline film conductivity in terms of the reduced
thickness k and the grain‐boundary reflection coefficient r. Numerical tables are given to show the agreement of the
above expression with the Mayadas‐Shatzkes expression.
Underwater Acoustic Measurements on Polyvinylidene Fluoride Transducers
Authors: Woodward B. , Chandra R. C.
Published: June 2007

Methods of making piezoelectric transducers from very thin sheets of polyvinylidene fluoride (PVDF) are discussed,
together with techniques for calibrating these devices, particularly for underwater operation. Parameters measured
include receiving response, source level, beamwidth, characteristic impedance and variation of impedance with
frequency. Consideration is also given to the dependence of receiving response on the poling fields and temperatures
used in making PVDF transducers. Because of their broadband response thin sheet PVDF transducers have been
shown to be ideal for monitoring the true form of acoustic pulses underwater.
Epoxies for Component Mounting in Thick Film Hybrids
Authors: Marshall C.
Published: June 2007

Specialist conductive and non‐conductive epoxies have been used in hybrid assembly since about 1970. Initially
they were used as an alternative to eutectic bonding for the mounting of semiconductor chips, but they are now
used for mounting a wide range of components. This paper looks at the performance of a wide range of epoxy
mounted components, and considers many of the practical problems arising from the use of epoxies in production.
Improvement of Adhesion, Line Definition, Contact Resistance and Semiconductor Properties by Sputter‐Etching
Authors: Kallfass T.
Published: June 2007

In an RF‐sputtering unit, with suspended substrates mounted in lieu of a target, sputter‐etching of the substrates
and consecutive vapor deposition of Au is performed in order to achieve good adhesion of the Au‐film without an
adhesion layer. The method has been applied for surface‐acoustic‐wave filters on piezo ceramics and for noise
measurements in Au‐films on sapphire. The sputter‐cleaning as described also reduces the disturbing contact resistance
between the conductive Cr‐Au‐layers and the previously sputtered Ta‐film.

Considerable progress has also been made in the manufacture of thin‐film transistors by photolithography,
chemical etching, and sputter‐etching instead of using evaporation masks.
The Frequency Dependence of Resistance in Foil‐Wound Inductors
Authors: Murgatroyd P. N. , Walker N. J.
Published: June 2007

Foil wound air‐cored inductors are widely used in power electronics applications, and often exhibit power dissipation
much greater than can be accounted for by the d.c. resistance. This is shown to be due to non‐uniform current flow.
A scaling rule, relating the effects to turns and frequency, is demonstrated. The general principle of equal current
sharing can be satisfied in a toroidal system.
Electrical Properties of Epitaxial Aluminium Films
Authors: Dobierzewska-Mozrzymas E. , Warkusz F.
Published: June 2007

The resistivity of monocrystalline Al films was measured and compared with the resistivity calculated in terms of
the function which takes into account both the external and the internal size effects. A comparison of the
theoretical and experimental curves shows that the specular reflection coefficient (p) is small, while the
coefficient of electron transmission through the grain boundary (r) increases with increasing film thickness.
Hybrids in Telecommunications
Authors: Roggia D.
Published: June 2007

The telecommunication industry has greatly contributed to the diffusion of hybrid technology in all electronic fields.
The approach, followed by almost every telecommunication company, in order to optimize the implementation of
hybrid circuits, is to use both thin and thick film technologies. After a short review of the characteristics of the
telecommunication market, which affect hybrid technology, the adaptive and simple but powerful approach of
Telettra will be presented.
Some Aspects of Multilayer Ceramic Chip Capacitors for Hybrid Circuits
Authors: Noorlander W.
Published: June 2007

It is shown that both European and American standardization committees specify the dimensions in the same
grid and that there is no standardization of the thickness in relation to the capacitance.

Of the ceramic dielectrics, special attention is paid to the instability of capacitance and losses of type II
materials due to temperature and voltage treatment.

The conductivity of the inner electrodes determines the losses at 1 MHz in type I dielectrics. It is shown
that the economically interesting partial replacement of Pd by Ag can cause an increase in the losses: other
substitute metals seem more promising.

The last aspect discussed is the end terminations of the capacitors. In the case of silver/palladium end
terminations the Ag/Pd ratio should be smaller than two.
Thin Resistive Thick‐Film Layers Based on Precious Metal Resinate/Glass Systems
Authors: Prinsen P.
Published: June 2007

This paper describes the preparation and results obtained with a ruthenium‐resinate/glass resistive system prepared
by firing on to a 96% alumina substrate. The results have been compared with a gold/rhodium‐resinate/glass system. It
is found in the ruthenium system that the particle size is about 200 Å and because of this, conduction occurs at a
very low volume percent conduction phase. Temperature Coefficient of Resistance behaviour of the ruthenium
based system is still anomalous.
The Structure and Properties of Reactively Bonded Thick Film Gold Conductors
Authors: Coleman M. V. , Gurnett G. E.
Published: June 2007

The properties of reactively bonded gold conductors have been compared with a fritted gold conductor (DuPont
9260). Several different additives in the gold conductors were examined, including copper/copper oxide; copper
plus cadium/germanium and copper cadium and bismuth.

The adhesion strength of all the conductors was found to be superior to the fritted standard, but the electrical
conductivity did not appear to be improved. These materials thus offer advantages where stronger adhesion is
required or possibly, where the interface between conductor and substrate needs to be well‐defined.
Functional and Deterministic Tuning of Hybrid Integrated Active Filters
Authors: Moschytz G. S.
Published: June 2007

The two main methods of tuning hybrid integrated active filters, namely functional and deterministic tuning are
described. Functional tuning implies the fine adjustment of an active network that is assembled and in operation
so that its transmission characteristics (e.g. gain or phase response) can be monitored during the tuning process.
One or several resistors are selected as tuning elements and these are adjusted (e.g. by laser, anodization, sand‐blasting,
“postbox” selection of discrete resistors) until the desired response is obtained. Deterministic tuning
involves the fine adjustment of individual resistors to values which are analytically predicted. The prediction is
based on network equations which include parasitic effects and in which those component values that are not to be
adjusted are obtained by measurements on the (non‐operational) manufactured circuit. Manufacturing tolerances
and parasitic effects are included in the comprehensive set of equations whose solutions provide the final adjustment
values of a few ‘tuning resistors’. Accuracy bounds and limitations of the two tuning methods are given and the pros
and cons of the two methods are discussed. Finally it is suggested that a well balanced combination of the two
methods may well provide the most efficient and least complicated solution to the tuning problem in hybrid
integrated networks.
The Development of Precision Thin Film Resistors for Submerged Repeater Applications
Authors: Spiller D. O.
Published: June 2007

The paper describes development of a low inductance thin film resistor series with a stability of ±0.15% change in
resistance, over a 25 year life, in a submerged repeater environment. (40% RH maximum and 0 to 30℃ ambient
temperature).

It was first necessary to establish an appropriate mathematical model relating resistor stability with time and
temperature. This was devised from experimental data based on measured resistor drift at various temperatures, and
enabled acceleration of resistor drift to be carried out to ensure that each resistor possessed the required stability.

Deposition of a secondary nichrome layer protects the gold/nichrome interface and promotes SiO2 adhesion.
This results in an improvement in the basic elevated temperature resistor stability by minimising diffusion effects of
nichrome into the conductor, and protection against electrochemical corrosion as demonstrated by 10,000 hours life
test at 83% RH @ 28℃ on 5 mW load and by elevated temperature tests under electrical loading.
Nonlinearity Measurements Using Alternating Current
Authors: Ryšánek Vladimír , Corsi Carlo , d′Amico Arnaldo
Published: June 2007

The nonlinearity measurement technique described uses an adapted conventional lock‐in‐amplifier. This technique
enables us to measure small nonlinearities over a wide frequency band and is more sensitive than the 1/f noise
measurement used to detect non‐homogeneous structures in conductors, resistors and semiconductor components.
Results illustrating uses of this method are presented for different types of resistor and semiconductor structures.
Thick Film Thermal Print Heads
Authors: Barnwell Peter
Published: June 2007

Thermal print heads are finding widespread application in equipment as diverse as pocket calculators, chart
recorders, and computer page printers. The use of thick film resistors to mark paper is one of the more common
techniques and the design problems and performance available from such heads are the subject of this paper. Future
developments of the technology are also discussed.
Hybrid Electronic Watt‐Hour Meter
Authors: Trontelj J. , Trontelj L. , Jan F. , Hrovat M.
Published: June 2007

An electronic watt–hour meter in hybrid thick and thin film technology is described. Benefits of combined hybrid
technologies are evaluated. Methods for offset voltage and multiplier modulation frequency are given. The hybrid
circuit with the 10−5 linearity for a 0.1 class electricity meter is shown.
State of the Art in Design and Technology of SAW Devices
Authors: Lagasse P. E.
Published: June 2007

In this paper the different classes of surface acoustic wave devices are briefly reviewed and examples of the state of
the art are given. The fabrication techniques and the application of SAW components are also discussed.
Materials and Applications for Thin Films in Hybrid Microelectronics
Authors: Zinsmeister G.
Published: June 2007

The use of thick films in microelectronics has increased in an impressive way during the last years. In contrast to this,
thin films have shown a less spectacular but nevertheless steady evolution which concerned mainly more efficient
deposition methods (planar magnetron) as well as higher quality films and thus better components and circuits. The
present paper aims at illustrating this by some selected examples.
A Computer Programme With Temperature Gradient Capability for theNetwork Analysis of Hybrid Circuits
Authors: Zimmer Carl R.
Published: June 2007

A modified version of the computer programme SINC‐S is described which permits the user to specify independently
up to 30 different device temperatures in a given problem when the proper control statement is included. An
additional option is an algorithm for the steady‐state solution of a non‐linear network with periodic inputs, so that
realistic system operation may be simulated. The programme may be used to provide more accurate simulation of
circuits where large temperature gradients are present, and to furnish input data for other thermal analysis
programmes
Tantalum Thin Film Capacitors With Various Types ofCounterelectrodes
Authors: Ferraris G. P. , May R.
Published: June 2007

Capacitors have been prepared from N2‐doped, triode sputtered Tantalum films by conventional anodization and
photolitographic techniques.

NiCr–Au, Ta–Ti–Pd–Au, Ta–NiCr–Pd–Au have been used as counterelectrode materials and the a.c. and d.c. properties of the capacitors have been compared.

It has been found that a doped Ta thin layer deposited by sputtering between the dielectric and the top electrode
does not negatively affect the capacitors characteristics; moreover, a thermal treatment at temperatures as high
as 350℃ can be tolerated.

If the Ta film deposited after the dielectric formation is used for resistive elements, a fully compatible R–C
process is obtained which requires only two vacuum deposition cycles and four photolithographic steps.
Some Observations on the Accelerated Ageing of Thick‐Film Resistors
Authors: Sinnadurai F. N. , Spencer P. E. , Wilson K. J.
Published: June 2007

Methods of accelerating the ageing of thick‐film resistors (TFRs) have been explored, with encouraging results from
experiments in which elevated temperature and damp heat were inflicted on TFRs. Consistent acceleration was
obtained by increasing temperature, whether by storage or dissipation, the activation energies for thermal ageing of
various resistor families lying in the range 0.5 eV–1.5 eV. Acceleration by humidity (RH) was also obtained,
corresponding, for example, to a halving of life for a 20% increase of RH, some resistance changes being about an
order of magnitude larger than those obtained at elevated temperature. The encapsulations played a dominant role
in the degradation of resistors under both stress conditions.

According to the theories of conduction, degradation could occur because of reactions at conductive sites,
causing corresponding changes in the conductivity and resistance versus temperature (R(T)) characteristics.
Progressive degradation certainly did occur, as evidenced by the conformity of the ageing behaviour to a diffusion‐type
(time)1/2 dependence accompanied by shifts in the R(T) characteristics. Some interpretation of the
degradation has been possible by referring to an empirical model of the temperature dependence of resistance, but
conflicting changes can be reconciled with the model only by postulating competing degradation mechanisms. The
report covers an early stage of the work.
Influence of the Substrate on the Electrical Properties ofThick‐Film Resistors
Authors: Cattaneo A. , Pirozzi L. , Morten B. , Prudenziati M.
Published: June 2007

The effect of substrate type on the electrical properties of thick film resistors is determined. Five different
substrates are used. The following properties are investigated: – thermal expansion, resistor profiles, resistance,
TCR and resistor gauge factor. The resistors are physically inspected using X‐ray diffractometry and electron
probe analysis. This paper shows that conduction mechanism models for thick‐film resistors generally need not
take into account chemical and structural interactions with the substrate. However the effect of substrate on TCR
values is significant for resistors exhibiting a large piezoresistive effect.
An Improved Thick Film Aluminium Conductor Process
Authors: Cooper R. E. , Linford P. F. T. , Savage J.
Published: June 2007

Aluminium thick film conductors offer very large cost advantages compared with noble metals and can also improve
the reliability of circuits by eliminating gold‐aluminium interfaces and their attendant intermetallic phenomena. To
date however, it has not been possible to produce aluminium thick film conductors which are ultrasonically
bondable to aluminium‐silicon wire.

This paper describes a study of the microstructure and line profile of a commercially available aluminium thick
film paste as a function of firing schedule. Scanning electron microscopy has revealed the mechanisms which control
the sintering process and has suggested a revised firing schedule. It is shown that firing schedules exist which yield
conductors with adequate ultrasonic bondability and conductivity. The results of bond ageing experiments on bond
strength and conductivity are given for periods of up to 1200 h at temperatures of 60–200℃.

It is shown that bonds of aluminium wire to aluminium thick film are resistant to loss of bond strength but suffer
from loss of conductivity on ageing at 150℃.
How International Component Standardisation Affects Specificationand Design Work in India
Authors: Goswami Amit P.
Published: June 2007

The specification systems available to the Indian component manufacturers are discussed and the influence these
have on the markets are examined. Quality control methods used to meet specifications are noted.

The influence of the Indian Government′s pricing policy on the encouragement of indigenous production of
components has an important effect, particularly with regard to the export and import of components. The
differences that exist between component groups are outlined and it is shown that there are still important areas
where overseas collaboration is encouraged.
On the Sensitivity of Canonically Extended RC‐Active MultiloopFilters
Authors: Massara R. E.
Published: June 2007

A class of multiloop active filters based on a double RC ladder of simple recurrent structure, constrained by a single,
positive gain, voltage‐controlled voltage source has received recent attention in the literature.

Some design considerations are discussed in this paper and sensitivity results are presented which permit
comparisons to be made between filter realizations with different types of capacitance spread constraints. It is
shown that the common practice of constraining all capacitors to be equal leads to high sensitivity and that, by
relaxing this zero‐spread requirement, much more favourable sensitivity results can be obtained.
Screen Printed Metallization of Silicon Solar Cells
Authors: Frisson L. , Lauwers Ph. , Mertens R. , Van Overstraeten R. , Govaerts R.
Published: June 2007

This paper presents a screen printing process for the metallization of silicon solar cells. The physics and construction
of a classical solar cell are reviewed. The results obtained with a screen printing process are comparable with other,
more expensive technologies. This technology does not introduce an additional contact resistance on silicon. The
process optimization and the influence of different parameters are discussed.
Sintering Mechanisms in Base Metal Conductors
Authors: Degraeuwe J. , Brauns E. , Van Overstraeten R. , Roos J. , Govaerts R.
Published: June 2007

Thick film conductors based on Al, Cu and Ni have been studied. Because of its high depth of field, a SEM was
used to study the microstructures of the fired conductors.

Because of the very small size of the particles in commercial Cu pastes the neck growth forms part of the grain
growth mechanism.

The bonding between the particles is much stronger in Cu than in Al films; this seems to be the reason why the
sheet resistance of a Cu film virtually reaches the theoretical minimum.
Functional Trimming of Thick‐Film Active Filters for Consumer and Industrial Applications
Authors: Dell′orto Giuseppe , Ravaschio Guglielmo
Published: June 2007

Active filters, realized in thick film circuitry, can offer major advantages over more conventional wiring systems,
including the ability to functionally trim them, using a computerized laser trimming system. This paper considers
the adjustment methods used for two different active filters and shows how the methods can be extended to filters
with more complicated characteristics.
Transient Phenomena in Sputtered CdS Photocells
Authors: Piel A. , Murray H.
Published: June 2007

We describe experimental data and theoretical studies of response time measurements in sandwich structures
Al—CdS—Au. The speed of response is about 2 μs in a large sensitivity range. A theoretical simplified model shows
that this response time is limited by the majority carrier lifetime. The concept of photoconductive gain G which
represents the ratio between the carrier lifetime τn and the transit time tn seems to be particularly well adapted to
describe specific properties of very thin photovoltaïc cells.
Influence of Electrolytes in the Electrical Characteristics of Anodic Films on Tantalum
Authors: Fernández M. , Baonza J. , Albella J. M. , Martínez-Duart J. M.
Published: June 2007

The electrical characteristics of anodic oxide films formed on tantalum are investigated in anodes oxidized in the
standard electrolytes for low‐voltage (0.01% H3PO4 in water) and high‐voltage (same plus ethylene glycol)
applications. It is found that small additions (about 0.1%) of certain organic acids such as citric acid to the above
electrolytes greatly improves the leakage current, the scintillation voltage and the dielectric losses of tantalum
capacitors. Furthermore, the use of these organic acids makes it possible to extend to higher voltages the use of the
low‐voltage electrolyte, and allows, in the case of the high‐voltage electrolyte, a substantial diminution in the
ethylene glycol concentration without impairing the characteristics of the resulting capacitors. Finally, the effect of
the citric acid and the ethylene glycol in the anodizing electrolytes is discussed.
Ni‐P as a New Material for Thick Film Technology
Authors: Barycka I. , Hołodnik B. , Misiuk A.
Published: June 2007

The product of nickel ions reduction in buffered solution by hypophosphite, known as Ni‐P, was examined as a
potentially useful material for thick film technology. This material, when mixed with glass oxidizes if heated above
450℃ in an air atmosphere. For this reason we investigated the possibility of using an additive to stabilize the Ni‐P
against oxidation. We found that B2O3 as an additive showed itself to be most satisfactory. A detailed investigation
of the phase relations in heated Ni‐P, Ni‐P‐glass and Ni‐P‐glass‐B2O3 compositions was performed. The inks
prepared so far from the mixture of Ni‐P‐glass‐B2O3 can only be used in thick film technology for conductor layer
production (R□∿0.1Ω).

The most satisfying and practically useful characteristics were obtained for inks produced from solid
components containing 45 to 80 wt% Ni‐P and about 10 wt% B2O3.
Design and Production of Hybrid Circuit Artwork
Authors: Milne A. D.
Published: June 2007

The demand for greater complexity in hybrid circuits requires new techniques to be applied to the production of
artwork. The paper discusses the use of a high precision pattern generator and the relevance of integrated circuit
CAD software to the production of hybrid circuits.
Permanent Interconnection Technology
Authors: Campbell D. S. , Boswell D.
Published: June 2007

This paper is concerned with the permanent connection of electronic components into sub‐systems and is based on
the report of an ERC Working Party that investigated the subject during 1978 and 1979. After an initial description
of the interconnection concepts and the relationship the field has to electronic assembly systems in general, a survey
is given of the marketing data that is available that defines the economic importance of the field. This survey
includes new data obtained by the Working Party. Figures are given for the rest of Europe in general and the UK in
particular and it is noted that the Output at Sales Value in the UK of intereconnection technology products is almost
the same as the Output at Sales Value of ICs in the UK. Within permanent interconnection technology two‐thirds of
the Output at Sales Value is associated with PWBs and one‐third with thick/thin film circuits.

Research Work in the field is discussed and a division between immediate time scale problems and those involving
a longer time scale is suggested. Twenty‐nine immediate time scale R & D problems have been recognized covering
all three interconnection technologies; longer time scale problems will be associated with the continuing decrease in
the size of add‐on electronic components.

It is concluded that large, fast computer systems will require a decrease in the size and spacing of interconnections
to match those of the semiconductor chip. This means simultaneous design of semiconductor and
associated interconnection structures tasks well‐suited to vertically integrated companies. In contrast, many real
time subassemblies will benefit from greater chip complexity and need fewer outgoing leads per chip, i.e. at wider
spacings – needs that can be met by the development of existing techniques. Finally it is suggested that future
distribution of added value in electronic assembly operations is likely to give all sectors of interconnection business
a steady upward sales trend, with both hybrid and semiconductor manufacturers seeking specialized subsystems
markets to replace their present “all things to all customers” policies.
Hybrid Amplifier Modules for Nuclear Measurements in Space Flight Experiments
Authors: Funk Walter , Winkelnkemper Wolfgang
Published: June 2007

Nuclear electronic instruments for the measurement of the precise energy and time‐of‐flight of charged particles, e.g.
heavy ions, are quite often present on scientific satellites. In addition to the non‐trivial electrical requirements, size,
weight, and power consumption have to be kept within strict limits for space flight electronics. Furthermore, such
instruments must possess a wide operating temperature range and resistance to irradiation. In the interest of cost
effectiveness it is desirable to develop modules with a sufficiently wide application to enable their use on more than
one mission. Because of the small quantities (expected need is in the order of some hundred circuits per year) and
the resistance and capacitance values required, a hybrid thick film approach is considered to be the most economical
solution. The development of two amplifier modules took place in a co‐operation between the Max‐Planck‐Institut
für Aeronomie in Lindau/Harz (scientific and environmental requirements), the Hahn‐Meitner‐Institut Berlin
(irradiation treatment), the Lehrstuhl für Elektronische Schaltungen of the Ruhr‐Universität Bochum (electrical
design), and the Philips Forschungslaboratorium Hamburg (technological implementation and production of
prototypes). The results and experiences are reported in this paper.
The Solution of Two‐Dimensional Heat Conduction Problems for Predicting Operating Temperature andPower Handling Capabilities of Hybrid Circuits
Authors: Ferraris G. P. , Tudanca M.
Published: June 2007

The problems of heat conduction in hybrid thin and thick film circuits have been investigated using both
analytical and numerical approaches.

The calculations were restricted to two dimensions by assuming zero temperature gradient across the thickness
of the substrate (slightly more than half millimeter).

All normally recognized parameters were taken into consideration, such as film temperature, power dissipated,
substrate area, etc.

Allowances have also been made for lead conduction and connection technology, for horizontal or vertical
circuit assembly, and for flush or stand‐off mounting on the mechanical support.

The measured results for practical cases show close agreement with the theoretical calculations.

This approach provides a simple tool for the calculation, at an early design stage of power handling capacities
of hybrid circuits using composite resistive configurations.

Very little difference was found between temperatures predicted from the theoretical approach and those
measured in practical cases of circuits under load.

The availability of such accurate design information means that the stability, life, and reliability of hybrid
circuits can be predicted with considerable accuracy at an early design stage.
Development of Substrate Carrier System
Authors: Miura N. , Fuura Y. , Uchida K.
Published: June 2007

The Substrate Carrier System (S. C. System) is a new manufacturing technique for small size hybrid IC with IMST
(Insulated Metal Substrate Technology)substrate which is used for power hybrid IC (STK series). The point of this
system is to treat both substrate process and assembly process in the manufacturing process of hybrid IC, with several
IC substrates at the same time. In the printing process, multi‐IC pattern are made on a large IMST substrate at the
same time and the substrate after completion of printing process are slit‐punched to have the frame configuration
where individual IC substrates are conected by tie‐bar. Moreover in the assembly process which involves
die‐bonding and wire‐bonding, the substrate is carried by the pitch of IC substrate, utilizing the frame construction,
which can provide the automatic processes.

This Substrate Carrier System is applied to many kinds of hybrid IC for low‐frequency applications as a system of
high reliability and productivity.
Selective Glaze for Last Line Visible Thermal Head
Authors: Hashimoto Kaoru , Kamehara Nobuo , Terashima Minoru , Niwa Koichi
Published: June 2007

A thermal head in which the last line is visible allows characters to be viewed as soon as they are printed. The thermal
head is constructed with a selective glazed layer and heat sources, which are formed at the edge of a ceramic
substrate. The selective glazed layer must be smooth and flat, even at the edge, for heat sources to be formed on it.
Selective glaze characteristics were studied using PbO‐B2O3‐SiO2 and B2O3‐SiO2 glazing materials to realize the last
line visible thermal head. Several commercially available gold conductors were screen printed on fine grained alumina
substrates. Wettability, levelling characteristics and flatness at the edge of the selective glaze on each gold conductor
were examined. Dependence of their characteristics on firing conditions were also examined. A combination of
PbO‐B2O3‐SiO2 glass and fritless gold conductor provides a smooth and flat glaze surface even at the edge, and experimental results show that PbO‐B2O3‐SiO2 glazing material has the most suitable characteristics for a last line
visible thermal head. A last line visible thermal head was formed using PbO‐B2O3‐SiO2 glazing material. The selective
glazed layer was formed over the thick film circuits of gold for the power supply, which were screen printed on a fine
grained alumina substrate. Ta2N thin film for resistive heat sources was formed at the edge of the glazed layer. The
thermal head provides good print quality and can print 20 characters/line at 5 lines/sec with a resolution of
2.7 dots/mm.
IC Packaging Technology for Electronic Watches
Authors: Iinuma Yoshio
Published: June 2007

IC‐Quartz watches have been manufactured since the appearance of CMOS‐LSI about seven years ago. Nowadays,
the outside view of the quartz watch is the same as that of a mechanical watch through minimizing electronic parts such
as battery, crystal oscillator, capacitor, and IC packaging volume. Recently, IC packaging technology for electronic
wrist watches (both the analog quartz watch and digital quartz watch) has made a step foward. In Japan, some watch
makers adopt a film carrier assembly technique for producing thin and low‐priced watches. They are using 3 layers and
35 mm wide film which fits very well the substrate of the quartz watch, especially the digital quartz watch.

The Citizen Watch Co., Ltd. started an investigation as to which method was suitable for IC package for watches in
1975 and adopted a flip chip technique as being the most suitable for analog quartz watches. The flip chip technique
will allow the fabrication of a very small and thin package. Important characteristics of the technique permit design
flexibility and high density packaging of the ICs. In this paper, a flip chip technique using a Printed Circuit Board as a
substrate is described.
Copper Materials System for Microcircuitry: A Status Report
Authors: Mitchell J. D. , Donohue P. C. , Needes C. R. , Funer R. E. , Uhler R. O.
Published: June 2007

The electronics industry has become interested in a thick film materials system based on copper for both technical and
economic reasons. Copper conductors offer excellent conductivity, solderability, and solder leach resistance as well as
lower intrinsic metal cost and price stability.

Significant adoption of copper in thick film applications requires a complete system of materials for the designer and
manufacturer to choose from and sufficient processing information to assist the industry to get started. Industry has
begun the adoption of copper in selected applications. Design of new applications and experience in processing will
move this technology forward in the industry.

Du Pont has developed a copper materials system which includes copper conductor compositions, low K dielectric
and compatible resistor compositions. The compositions are screen printed, dried in an air atmosphere at 120℃ for
ten minutes and fired in a nitrogen atmosphere to a peak temperature of 900℃. All materials in the copper system
may be processed in commercially available atmosphere conveyor furnaces using commercial nitrogen.

The copper compositions provide high adhesion conductors with resistivity values in the range of one to two
milliohms per square. They can be used to make multilayer interconnect structures, microwave circuits, and as a
replacement for Mo‐Mn metallizing. In addition, copper may be used as the conductor on porcelain‐enamelled steel
substrates. The dielectric composition provides a dense film with a dielectric constant of about eight which can be used
With copper to make multilayer interconnect structures. The resistor compositions produce resistors with temperature
coefficient of resistance (TCR) less than 150 ppm per ℃ and are useful for resistor networks and hybrid microcircuits.
Fundamental Characteristics of Solvent–Soluble Polyimide Resin as aPolymer for Hybrid Applications
Authors: Watanabe Eiki , Kanou Kyoichi , Kubota Tadashi
Published: June 2007

Polyimide resin of solvent‐soluble type, which is called “X‐resin” in short, was discovered lately. It is soluble in
dimethylacetoamid (DMAc), and new extensive applications are expected.

Some physical, chemical and electrical characteristics are studied from the viewpoint of polymer material for hybrid
application. Particularly comparison of the characteristics of X‐resin specimens before and after long term exposure
to humid and hot environments were made, remembering that electronic devices often operate under such conditions
in Japan.

From the results obtained up to now, no conspicuous difference seems to exist between the characteristics of X‐resin
and those of the conventional (i.e., solvent‐insoluble) resins, as published in various literature. It should be noted,
however, that some unusual effects, i.e., the remarkable increase in surface resistivity σ, the evident decrease in tan δ,
etc., were found in X‐resin specimens after going through the above‐mentioned damp‐hot test. All those effects are
contrary to the usual concepts of deterioration of polymer materials, but are rather advantageous for hybrid
application. It is also worth noticing that silver migration into X‐resin seems scarcely to occur.

Furthermore, new prospective uses of X‐resin for printed wiring boards, packaging materials, binder for paste
materials, etc., are investigated.
Failure Mechanisms That Cause High Electrical Leakage in MultilayerCeramic Capacitors
Authors: Ikeo Hirofumi , Sakamoto Sanpei , Sato Ken , Nishiura Hisakazu , Ohno Katsuhiro
Published: June 2007

The causes of failure mechanisms of multilayer ceramic capacitors that result in zero resistance (shorts) or low
resistance (high leakage) behaviour in the capacitors when the capacitors are subjected to low voltages have been
studied. It has been found that failures resulted from the electrochemical reaction of electrode materials in the
microscopic open pores which pass across a ceramic layer between inner electrodes and are filled with water
containing Cl− ions. The mechanism found in this investigation has been applied to enable screening processes to be
evolved for manufactured capacitors to eliminate the possibility of failure and hence to improve the reliability of
circuits using multilayer ceramic capacitors.
The Effect of High Speed Laser Trimming on Accuracy and Stabilityof Thick Film Resistors
Authors: Coté René E.
Published: June 2007

Many recommendations have been made on the proper operating conditions for the laser trimming process. In
general these recommendations have centered on accuracy, precision or throughput. In some instances, these have
appeared to be mutually exclusive. If one wanted accuracy and precision, one had to sacrifice trimming speed and,
therefore, throughput.

It has been reported that 40% of the processing cost of a thick film resistor network is due to laser trimming. To
continue to make these networks commercially attractive, the manufacturers of laser trimming systems have addressed
themselves to the problem of providing suitable cuts at higher and higher trimming speeds.

It is important for the user of such a system to understand the basics of the trimming process and to have an
appreciation for the new factors which will affect the performance characteristics of laser trimmed thick film resistors.
This paper summarizes the previous work as it relates to present technology. It then attempts to develop new
guidelines for high speed laser trimming.
Heat Treatment of CdSe Thin Films and Application to Photopotentiometers
Authors: Sato Masuji , Kawai Satoru , Yamada Fumiaki
Published: June 2007

Effects of heat treatment have been studied in a nitrogen atmosphere for improving the characteristics of poor
photoconductive CdSe evaporated films. The following results were obtained. At first light resistance and dark
resistance greatly decrease after the heat treatment of evaporated films in a pure nitrogen atmosphere for an hour.
The ratio of dark resistance to light resistance under irradiation of 1,000/ux remained as low as an order of magnitude
of 10. Secondary increase of an order of magnitude of 106 or 107 in dark resistance is obtained, adding to the post
treatment in N2 + O2 atmosphere for thirty second after the main heat treatment in N2 for an hour. The ratio of dark
to light resistance becomes an order of 108 and as for photoresponse, both rise and decay time of photocurrent
become 0.5 ms. The results indicates that heat treated films have characteristics of good photosensitivity and quick
response in photocurrent.

The photopotentiometer has been analysed by using the transmission line theory and device input–output
characteristics have been related to the properties of the resistive film and photoconductive film of the device.

The photopotentiometer using the improved photoconductive CdSe thin film has been fabricated and examined.
A good independent linearity of less than 2% at a speed of 2000 rpm is obtained.
Solder Paste Process of Hybrid Circuits
Authors: Takasago Hayato , Adachi Kohei , Ohnishi Youichiro , Tazuke Kazuo
Published: June 2007

This paper describes the critical factors required for the solder paste process and its applications to Hybrid Circuits
(Solder Paste Process). It also describes the fine solder printing of substrate pads for flip chip IC and the
simultaneously thick printing of solder paste for chip capacitors and/or other parts.

Through this “Solder Paste Process”, assemblies of good quality and higher yields are achieved. The results of
various evaluation and reliability tests were excellent. From this study, some new applications of solder paste are
presented.
Minicomputer Interactive System for Hybrid Automation
Authors: Sansen W. , Govaerts R. , Heyns W. , Beke H.
Published: June 2007

A computer‐aided layout program MISHA has been developed for the layout of thick‐film substrates. The program
consists of several modules to carry out the various steps involved in the layout process. A complete layout is produced
starting from a library of available components and the network‐description of the circuit. Manual interference of the
user with the program is possible at every step in the layout process. The program is written in standard FORTRAN
IV and runs on a PDP 11/40 minicomputer.
Automatic Production System for Circuit Boards With Universal HybridIntegrated Circuits
Authors: Ohsawa Mitsuo
Published: June 2007

In the 1970′s, much development occurred in monolithic IC′s and automatic insertion machines, which brought about
extensive changes among mass producers of electronic consumer products and greatly influenced the improvement of
quality and the saving of labor in production. The challenges of the next era are the achievement of the following four
objectives in addition to the quality improvement and labor saving objectives involved in the recent decade. 1) The
efficient use of material resources to eliminate waste, 2) elevation of reliability, 3) striving for uniform specifications for
components on a worldwide basis to achieve more rational and efficient operations, and 4) the creation of unique
products through new mounting and assembly techniques. Towards these objectives, a unique technology has been
developed which has been named ‘universal hybrid integrated circuits’ (UHIC), for which the automatic production
system has been put into practical use. The various components used in assembling through this system are cylindrical
in shape and entirely new in concept. They are called ‘metal electrode facebonding’ (MELF) type components. The
new production system has the capacity of mounting 600 components simultaneously and can handle circuit
boards up to a size of 330 millimeters per side. This means that a stereo unit or a color television set can easily be
assembled on one circuit board, which could be called “all‐in‐one UHIC”.
A New Type of Film Driver
Authors: Murata Masato , Akitake Shohei , Yamaguchi Hitoshi , Sasaki Hajime , Otani Shiro
Published: June 2007

A new type of film driver (NFD) has been developed using thin film integrated circuits technologies. The realized
driver was one‐tenth as small as that of a conventional driver in volume. The NFD has employed the tantalum nitride
(Ta2N) thin film resistors with low TCR values in order to achieve high accuracy. The NFD was housed in a
hermetically‐sealed metal case with a size of 39 × 26 × 6 mm. Resistors of NFD circuits were adjusted by laser
trimming. DC levels of the transistor circuits, were adjusted by functional laser trimming. When the developed NFD is
operated at medium output voltage of 4 Vp‐p for 5 years at circumstance temperature of 40℃, the resistance change
of the resistors which control the accuracy of the output voltage is predicted to be less than 0.05%, which corresponds
to the drift of the output level within 2 mV.