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dexterdev
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Hi,
Is solid state device physics a must learn subject to design analog circuits.
-Devanand T
Is solid state device physics a must learn subject to design analog circuits.
-Devanand T
f95toli said:If you are mean designing the components themselves (i.e. integrated circuits), then some solid-state physics might be a good idea.
dexterdev said:Is that really 'Some'...
dexterdev said:Is solid state device physics a must learn subject to design analog circuits.
f95toli said:It depends on what you mean by "circuit".
If you are talking about components on a circuit board, then probably no.
If you are mean designing the components themselves (i.e. integrated circuits), then some solid-state physics might be a good idea.
dexterdev said:Is that really 'Some'...
cabraham said:I recommend at least one semester of device physics.
rbj said:not all EEs who design ICs are designing the devices (the transistors, little silicon resistors, the MOS devices, etc.). many IC designers are circuit designers laying out the devices that other designers design onto the silicon and connecting them. that is 95% circuit design, very similar to if the devices were external on a PC board with some obvious exceptions (much shorter path lengths, coupling to substrate). then the answer is "Some", maybe very little.
but if you are designing the devices, the geometry of the device and the parts inside the device, the doping of the various parts, how many layers they are isolated from the substrate, the metal oxide parts, all of that design is more physics than it is circuit design. then you better know you ebers-moll equations and other similar models.
carlgrace said:It's very, very difficult to design high-quality integrated circuits without a pretty good understanding of how transistors work. Square-law MOSFET equations are pretty much fictitious by now.
You're right in that you won't need to know all that much about doping and carrier transport and the like, but you'll need to know a fair bit more about device physics than a PCB designer.
cabraham said:I recommend at least one semester of device physics.
berkeman said:I agree with this.
rbj said:whether the device is a transistor or something else, understanding how the device works is about doping and carrier transport and potential barriers and Fermi energies and the such.
understanding how to use the device is not the same. to use the devices, the physics you need to know about for lumped element circuits are Kirchoff's Voltage Law for each loop, Kirchoff's Current Law for each node, and the Volt-Amp characteristics for each element or device in the circuit. the rest is math. i am not saying that the circuit designer need not know how to do math, including dealing with non-linearities. and i am not saying the circuit designer need know nothing about the devices, he or she must know about the volt-amp characteristics and what parameters affect these volt-amp characteristics.
but the volt-amp characteristics is sort of the work product of the device designer, not the circuit designer. both of these engineers need to know something about what the other does, but it's the device designer that needs to know his solid state physics. the circuit designer needs to know the volt-amp characteristics, KVL, and KCL, and that person can do circuits.
if the circuit is on a common substrate, that circuit designer has to worry a little about the coupling (via a reversed-biased junction) to the substrate and how that might affect the behavior of the circuit. there is a very small leakage current and there is a very small capacitance. it's like every node in the circuit is connected to the substrate via a little reverse-biased diode or very tiny capacitor. at high frequencies that's a problem and the circuit designer needs to worry about that. but once the device designer gives the circuit designer the diode or ebers-moll or whatever V-A characteristics, i don't think the circuit designer need worry too much about the physics inside. as long as the devices are isolated.
carlgrace said:I don't mean to sound rude but have you designed many integrated circuits?
rbj said:quite alright. nothing analog.
i know it's different. I've been involved with an ASIC design and the Verilog guys never talked about the physical level, other than propagation delay. not within my hearing, anyway. they plopped down devices by writing logic and functional equations.
carlgrace said:You can't even get access to a bipolar process unless you work for one of a small number of companies
Solid state device physics is the study of the physical principles and properties of materials used in electronic devices, such as semiconductors, transistors, and diodes. It involves understanding the behavior of electrons and how they interact with different materials in order to design and improve electronic circuits.
Solid state device physics is essential for designing circuits because it provides a fundamental understanding of how electronic devices work. Without this knowledge, it would be difficult to design efficient and effective circuits that meet the specific requirements and limitations of different applications.
While it is possible to design circuits without a thorough understanding of solid state device physics, it is not recommended. Without this knowledge, you may not be able to fully optimize your circuit design or troubleshoot any issues that may arise.
A background in physics and mathematics is helpful for understanding solid state device physics. Familiarity with concepts such as quantum mechanics, electromagnetism, and material science can also be beneficial.
Solid state device physics can be applied in various ways in circuit design, such as choosing the right materials and components for a specific application, optimizing circuit performance, and troubleshooting issues. It also provides a foundation for understanding and learning about more complex electronic devices and technologies.