The following videos are a fun way to learn about silicon and semiconductors quickly!
Research Client Asks:
"I am looking at purchasing 100mm high resistivity silicon wafers. For my application, I need the wafers to have high carrier lifetimes (on the order of 100µs or greater), so I think they need to be float zone with high purity. The wafers can be undoped or have a slight n-type doping, along with <100> orientation. I will also be processing both sides of the wafer, so I will need double side polish. I am wondering if you have wafers that would suit my application?
I will be doing front side and back side DRIE with the wafers to micromachine waveguides. I need the high carrier lifetime as I will be exciting free carriers in the silicon using a laser."
The following wafers will work:
It is often asked: Does adding carbon to silicon monocrystalline lower the melt temperature? The answer is yes. Adding carbon increases the thermal conductivity and decreases the melting point of the material. The addition of carbon reduces the vapor pressure of the melt and increases the melting temperature. However, this process is only effective if the added carbon is not a part of the original crystal. Usually, carbon is incorporated into silicon before it is solidified.
The addition of carbon to silicon monocrystalline significantly lowers the melting point. However, it doesn't reduce the temperature of the monocrystalline material. It makes the material more resistant to heat. The melting point of this compound is lower than that of pure silicon, which is more brittle. In order to make it harder, it must be layered. This can be achieved through a process known as directional solidification.
The Scheil-Gulliver equation assumes that there is no diffusion in the liquid and the solid is a perfectly homogeneous liquid. In reality, there is no perfect homogeneity in the liquid, even with stirring driven by forced convection. Therefore, the impurities reject in the liquid during solidification tend to accumulate near the interface. To account for this, the effective partition ratio is introduced.
Using the Scheil-Gulliver equation, you can calculate the melting point of iron using the following information. The initial concentration of iron in the liquid is 1.5 x 1013 cm-3, the effective partition coefficient is 2 x 10-5, and the growth rate is 3.4 x 107 cm/s. For this experiment, the volume of silicon is filled up to 40 cm.
The melting point of iron is calculated from the effective partition coefficient of iron. The effective partition coefficient of iron is 2 x 10-5. This is the reason why the melting rate of the silicon is low. Its melting temperature is low compared to other metals, such as aluminum and copper. The iron dislocations are aligned along the dense direction. Then, the temperature of the ingot is lowered gradually.
The oxygen-carbon content of CZ silicon is the highest in the world. At its melting point, the concentration of oxygen is about ten 18 cm-3. It decreases several orders of magnitude at room temperature. Too much oxygen may cause unwanted electrical defects and thermal double donors. While carbon has some beneficial properties, it has negative effects on the melting point. Hence, it is not a good choice to add carbon to silicon monocrystalline.
Carbon is the second-highest concentration of oxygen in silicon. The oxygen-carbon concentration in CZ silicon is 5 - 1017 cm-3. This concentration is five times lower than the carbon-carbon level in monocrystalline silicon. The oxygen-carbon ratio in monocrystalline silicon is five-tenths of the smallest-atom silicon. The carbon-carbon ratio is five-tenths of the total silicon in CZ.
Adding carbon to CZ silicon will always decrease the melting point, but the atoms of carbon are not absorbed by the carbon. The oxygen-carbon ratio is approximately ten-eighth of that in the CZ silicon. The two elements are chemically similar. The carbon-carbon ratio is the most common in CZ silicon. It is the lowest of the two. The oxygen-carbon ratio is five-eighths of their normal concentrations.
As carbon is an impurity, oxygen has the lowest concentration in CZ silicon. This means that carbon is the highest-purity CZ silicon. But, carbon-carbon ratios vary from one to the other. The oxygen concentration in the CZ silicon is higher than that of CZ silicon. The CZ silicon has high oxygen-carbon ratio. It is a good example of a high-purity CZ material.
By adding carbon to the silicon monocrystalline, the crystals can be made with higher critical values. The lower the critical value, the higher the density of point defects. Both types of carbon are used in semiconductor manufacturing. During the production of integrated circuits, CZ-Si is more expensive than monocrystalline silicon. Its price is higher than CZ-Si. Nevertheless, the CCZ method does have the advantage of being a continuous source of molten polycrystalline silicon.
Below are just some of the books and videos to help you on your quest to learn about silicon.
Edited by S.S. Iyer and A.J. Auberton-Herve. https://books.google.com/books?id=n-xkaj7SWD0C&pg=PA359&lpg=PA359&dq=Silicon+Wafer+Bonding+Technology+for+VLSI+and+MEMS+applications.+Edited+by+S.S.+Iyer+and+A.J.+Auberton-Herve.&source=bl&ots=A3y4RubEoC&sig=ACfU3U1MOXHGJnJ_sy2j6ga97TpNoLRFCQ&hl=en&sa=X&ved=2ahUKEwi0v8vuqYHpAhVFgnIEHX4SBmoQ6AEwBnoECAgQAQ#v=onepage&q=Silicon%20Wafer%20Bonding%20Technology%20for%20VLSI%20and%20MEMS%20applications.%20Edited%20by%20S.S.%20Iyer%20and%20A.J.%20Auberton-Herve.&f=false
The effect of heating Silicon and allowing it to cool slowly to remove stresses and toughen the material is investigated. Thermal treatment increases the density and the native oxide thickness.
Technical information about the manufacturing of semiconductors. The process of wafer fabrication and the equipment used in order to fabricate a wafer are investigated.
The world of semiconductors and the studies associated with them are dynamic and exciting. As new developments are being made in the world of semiconductors the devices are becoming more complex.
This edition discusses the facets of quantum mechanical tunnelling with updated information. There are a large number of application problems with solved and unsolved exercises.
A thorough analysis of power semiconductor physics and how they are applied by the power electronics industry. Shows the operation for all power semiconductor devices.
A fully updated handbook on design processes and fabrication of MEMS, sensors, and other electronic devices. This is a full manual on the fundamentals of semiconductors.
In depth look at electrical properties and semiconductor characteristics. It brings together quantum mechanics and the theory of solids. A clarification of device physics.
Third updated edition to electronic, vibrational, transport and optical properties of semiconductors. An emphasis on understanding the physical properties of silicon.
A comprehensive look at the science and manufaturing of silicon materials. Completed with binary phase diagrams and practical applications like materials handling, safety and defect reduction.
A wide range of applications for semiconductor gas sensors in safety, process control and environmental monitoring. This is a full summary of emerging technologies in the semiconductor field.
Research Client Asks:
All bulk semiconductor crystals and wafers that are doped, have the dopant distributed in them as uniformly as possible. Considerable effort is made to measure both radial and axial uniformity of dopant distribution in a semiconductor ingot. CZ crystallized materials have large but predictable axial dopant variations and low Axial variation. FZ crystallized materials, gas phase doped, can have very low dopant variation throughout. Neutron Transmutation doping results in dopant variation dependent only on the uniformity of neutron Flux..
In making semiconductor devices on a bulk crystal substrate, doping is by diffusion (gas or liquid) through the wafer surface and therefore with inherent dopant gradient.
In Silicon wafers, I have not come across intentional co-doping with two or more elements.
In III-V semiconductors we have InP doped with both S and Zn. I have available GaAs:(Ga2O3+Cr), GaAs:(In+Sn), InP(Ga+Fe).
I have not ever come across Silicon doped with any III-V compounds, nor II-VI compounds.
I did come across GaAs:V2O5 and GaAs:Ga2O3.