7 ms·

> The fact that the other better semiconductors require large quantities of rare elements has been a very important reason that has prevented the replacement of

> The fact that the other better semiconductors require large quantities of rare elements has been a very important reason that has prevented the replacement of silicon in a large number of applications where it is an inferior solution. Maybe, but silicon is also damn good because of the adherence and dielectric nature of its oxide. Not to mention that several of the so-called superior semiconductors, even if you can get them in large quantities, are more difficult than silicon to crystallize without many defects. And silicon also conducts heat relatively well, meaning that it draws thermal energy away from hotspots within a chip better than some of the more expensive semiconductors. Not disputing the larger point about rare metals. Just asking you to put some respect on the name of my boy Si.

adrian_b 6y ago
You are right that silicon has many other advantages besides being abundant. Also correct is that the price of a semiconductor material in the form as it enters a semiconductor plant depends not only on the abundance of the raw material but also on how easy it can be purified and grown into crystals with very few defects. The latter 2 operations are indeed much easier for silicon than for compound semiconductors. Nevertheless, the choice of materials for any semiconductor device results from compromises between a very large number of properties and while silicon is good at some, it is worse at other properties, e.g. energy bandgap, breakdown electric field, velocity limits of charge carriers, electron mobility, leakage currents and others. So there are applications for which silicon may be the best choice, even if the cost of the materials is ignored. However, in more and more applications silicon continues to be used only because of its lower cost. It is likely that the use of silicon for the active part of the semiconductor devices will continue to decrease and this trend will accelerate. For example, to make faster CPUs, there are not a lot of remaining possible improvements. Three-dimensional silicon devices are a possibility for increasing the multi-thread performance, but only if it would become possible to circulate some liquid coolant through channels in the device, to eliminate the heat. Otherwise, the only chance is to use some other material than silicon for the active regions of the device. Even if the active semiconductor devices would be made from other materials, it is likely that silicon crystals will continue to be used as substrates long after that, due to the 2 advantages that you have mentioned, i.e. very few crystal defects and high thermal conductivity. For the record, I have worked for many years in a plant where silicon devices were made and I have handled thousands of silicon wafers, breaking just a few ;-( . Therefore, I actually have a lot of respect for your boy Si !

adrian_b 6y ago

You are right that silicon has many other advantages besides being abundant. Also correct is that the price of a semiconductor material in the form as it enters a semiconductor plant depends not only on the abundance of the raw material but also on how easy it can be purified and grown into crystals with very few defects. The latter 2 operations are indeed much easier for silicon than for compound semiconductors. Nevertheless, the choice of materials for any semiconductor device results from compromises between a very large number of properties and while silicon is good at some, it is worse at other properties, e.g. energy bandgap, breakdown electric field, velocity limits of charge carriers, electron mobility, leakage currents and others. So there are applications for which silicon may be the best choice, even if the cost of the materials is ignored. However, in more and more applications silicon continues to be used only because of its lower cost. It is likely that the use of silicon for the active part of the semiconductor devices will continue to decrease and this trend will accelerate. For example, to make faster CPUs, there are not a lot of remaining possible improvements. Three-dimensional silicon devices are a possibility for increasing the multi-thread performance, but only if it would become possible to circulate some liquid coolant through channels in the device, to eliminate the heat. Otherwise, the only chance is to use some other material than silicon for the active regions of the device. Even if the active semiconductor devices would be made from other materials, it is likely that silicon crystals will continue to be used as substrates long after that, due to the 2 advantages that you have mentioned, i.e. very few crystal defects and high thermal conductivity. For the record, I have worked for many years in a plant where silicon devices were made and I have handled thousands of silicon wafers, breaking just a few ;-( . Therefore, I actually have a lot of respect for your boy Si !