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1. Tuning Base and Collector Currents – All Regions

2. Tuning the Base Current – All Regions

3. Tuning the Collector Current – All Regions

4. The Base Current Profile – Medium Injection

5. The Base Current Profile – Low Injection

6. Conclusions

If you follow this order, there should be a reasonable correlation between measured and simulated data. Most of the tuning parameters, however, have some degree of interdependency to the extent of which is also device design specific. Therefore, some degree of iteration of the tuning parameters is to be expected.

When tuning bipolar transistors, there is a greater emphasis to accessing tuning parameters by using the device simulator, ATLAS, compared to optimizing MOSFETs, where most tuning parameters are process-related. A powerful combination is the tuning of a BiCMOS process where you can use the MOSFET part of the process flow to tune the process parameters, while using the Bipolar part of the flow to tune ATLAS. This technique should yield a high degree of predictability in the results.

Tuning the process simulator parameters in ATHENA are mainly required to model effects, such as the implantation induced defect enhanced diffusion responsible for the Emitter Push Effect, which is essential to obtain the correct depth of the base-collector junction. The correct process modeling of the out diffusion of dopant from the poly-emitter into the mono-crystalline substrate is also critical to obtaining well-matched I-V curves. Another critical process modeling area is the base implant, because it is essential to match measured and modeled base resistance for correct modeling of the collector current. These and other issues are discussed in these sections.

7.9.1: Tuning Base and Collector Currents – All Regions

The most important parameter to model the general level of base and collector currents is the device measurement temperature. The base and collector currents are strongly influenced by temperature changes, as small as a few degrees centigrade. A significant effort should be made to determine the exact temperature of the device during measurements before calibration is attempted. This temperature should be input into ATLAS in the MODELS statement using the TEMPERATURE=<n>parameter. An increase in temperature will cause an increase in base and collector currents.

7.9.2: Tuning the Base Current – All Regions

A critical region for poly-emitter bipolar devices is the interface between the poly-emitter and the mono-crystalline silicon. This region is difficult to process simulate directly as the interface between the polysilicon emitter and single crystalline silicon usually consists of a thin, uneven and possibly non-continuous film of oxide. This is simulated by calibrating the overall effect of this interface with ATLAS. The tuning parameter is the surface recombination velocity at this interface for electrons (VSURFN for PNP devices) or holes (VSURFP for NPN devices). This will only be effective for thin emitters where at least a fraction of the holes (for NPN devices) can reach the emitter before recombination.

Questions & Answers

Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
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Source:  OpenStax, Solid state physics and devices-the harbinger of third wave of civilization. OpenStax CNX. Sep 15, 2014 Download for free at http://legacy.cnx.org/content/col11170/1.89
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