QuantumATK Forum
QuantumATK => General Questions and Answers => Topic started by: Val on January 28, 2011, 08:35
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sir,
1.when implementing the gate in the continuum region,what is the material that is used in the metallic region (as it is not mentioned) and can we choose the workfunction for the same.
2.when a bias voltage of o.o1 is to be applied,how and where is this input to be given.
3.if Hfo2 is to be used as the dielectric what input should i give in the spatial region corresponding to it.(value) .
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1. The work function of the metalic region will determine where is the zero value of the gate potential. Thus, the effect of the work function is to shift the gate potential by a constant. You cannot set this parameter, and you need to make such corrections as post analysis.
I.e. work function of electrode is 4 eV, work function of gate is 5 eV, then you must add -1 V to you gate potential axis as post analysis.
2. You can set this parameter in the script generator tool in vnl, see forinstance the graphene device tutorial or the ATKDeviceTutorial
3 The dielectric constant of HfO2 is around 29 (many values can be found in litterature) consisting of an electronic part 6 and lattice part 23.
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1. The work function of the metalic region will determine where is the zero value of the gate potential. Thus, the effect of the work function is to shift the gate potential by a constant. You cannot set this parameter, and you need to make such corrections as post analysis.
I.e. work function of electrode is 4 eV, work function of gate is 5 eV, then you must add -1 V to you gate potential axis as post analysis.
2. You can set this parameter in the script generator tool in vnl, see forinstance the graphene device tutorial or the ATKDeviceTutorial
Can you please tell me how to determine the work function for electrode and gate for performing such post analysis :o
-- Thank you
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So is the default value for the metal workfunction of the gate 4eV?
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No, there was a small spelling mistake in that post. It should say "I.e. if work function of electrode is 4 eV...".
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Ok thanks. So regarding Ash's question, what is the workfunction of the metal gate and/or how is it determined exactly?
Regards.
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Please read kstrokbro's answer again. You need to know the workfunction yourself (i.e. you decide what the metal is), and adjust the values in the plots afterwards for it.