Silicon Carbide to Replace Silicon Wafers in Semiconductor Devices

university wafer substrates

We have a large selection of Silicon Carbide Substrates 4H and 6H epi ready.

You can buy as few as one wafer in diameters ranging from 5mm x 5mm up to 150mm.

Many are in stock and ready to ship.

Get Your SiC Wafer Quote FAST!


Our Silicon Carbide (SiC) wafers are used to fabricate High-Powerd Devices


Silicon Carbide (SiC) Semiconductor Market - By Device

  • Discrete Device
  • Diode
  • MOSFET
  • Module
  • Bare Die

Silicon Carbide Semiconductor Market - By Vertical

  • Telecommunications
  • Energy & Power
  • Renewable Energy & Photovoltaic
  • Automotive
  • EV
  • HEV
  • Military & Defense

I need 15-30 mm thickness and 4 to 8 inch diameter wafer, it should be clear and no pipes inside. Like crystal clear and full white in color. 

White Silicon Carbide Ingot for Moissanite Diamond

This super white SiC crystal is using for Moissanite Diamond,"clear and no pipes inside. Like crystal clear and full white in color".

white sic moissanite diamond

Please ask for pricing.

Silicon Carbide (SiC) Thin Films

Let us know how we can help you!

SiC thin films were grown onto polished p-type Si (100) wafers. Good crystallinity in the thin layers is desirable, as it affects different material properties. Since the sIC thin film deposits in amorphous nanocrystalline structures at low temperatures, a post-treatment such as annealing is necessary to improve the crystallination of the material.

Research shows that the ionized state is in the range of 0.5 - 1.1% of the total area, depending on the separation parameters and target composition. This seems to be very attractive, as it produces stuttering atoms and thus facilitates the formation of a crystalline phase. These properties allow the deposition of thin layers of nanocrystalline structures at low temperatures and the formation of thin layers with high - or low - pressure. Although there are no known techniques, the crystallinity of SICs differs considerably in the methods used, but low-pressure plasma-based techniques have been studied to enable deposition at room temperature, such as plasma-enhanced chemical dapor deposition and plasmionization.

Further details on the HiPIMS reactor are elsewhere, but the target is maintained at 3 mTorr, which is a flow rate of 20 sccm. The thin film is applied to an Aln buffer, which is equipped with a high-temperature, low-pressure and high-volume reactor (HV).

The carrier holder is held at a cutting time and a target value - the distance between the carrier material is set to 60 min or 60 mm, and 200 or 400 w are embedded for film growth. The floating potential of the film increases to 1.5 mTorr, with a float rate of 20 sccm and a floating potential ratio of 2.0.

Silicon Carbide Wafer Specs to Fabricate Power Devices

A scientist requested a quote for SiC wafers:

We need to practice etching and do not have other specs yet, but should mimic power devices. Can you recommend and quote? Can you thin 500um SiC wafers down to 350um?

UniversityWafer Replied and Quoted:

Power devices do not use 500um thick wafers; for 100mm products, a thickness of 350um is used.  Will this meet your

No Integrated Device Mfg  (IDM) wants to back-grind this 500um wafer down to a thinner level for device performance (On Resistance).  350um is the standard thickness that meets the need for shape control in the fab and thin enough to minimize the back-grinding process at the end of line.

Please ask for the specs and quote. Reference #254927.

4H Silicon Carbide (SiC) Wafers for Tunneling Microscopy

Researchers have used the following silicon carbide specs for their tunneling microscopy experiments.

 2" SiC 4H-N, Research grade SSP with higher conductivity

Silicon Carbide for Epitaxial Research

Researcher:

I am looking for both C-face and Si-face epi-ready 2inch diameter 4H-SiC wafer with 4 deg off-axis. I need n+doped and insulating from each. Also, I would like to inquire about 100 mm wafer price as a possible option for my work. These would be standard grade SiC wafers. 

UniversityWafer, Inc. Quoted:

Price depends on quantity.

  • both C-face and Si-face epi-ready 2inch diameter 4H-SiC wafer with 4 deg off-axis. n+doped,thickness 0.3-0.5 mm,as epitaxial substrate for growths
  • both C-face and Si-face epi-ready 2inch diameter 4H-SiC wafer with 0 deg off-axis. insulating,thickness 0.3-0.5 mm,as epitaxial substrate for growths
  • both C-face and Si-face epi-ready 4inch diameter 4H-SiC wafer with 4 deg off-axis. n+doped,thickness 0.3-0.5 mm,as epitaxial substrate for growths
  • both C-face and Si-face epi-ready 4inch diameter 4H-SiC wafer with 0 deg off-axis. insulating,thickness 0.3-0.5 mm,as epitaxial substrate for growths

Why are Silicon Carbide (SiC) Better than Sapphire and Glass for Bonding with Silicon?

A PHD student asked the following:

Actually, I know that sapphire and glass wafers can be used as carrier wafers, but I am wondering why SiC are used as carriers. What are they bonded to?

UniversityWafer, Inc. Replied:

SiC are used as carriers due to the good flatness and good thermal conductivity. SiC is better than sapphire and glass, as the silicon can bonded onto the SiC much more easily!

To learn more reference 262947.



Silicon Carbide Wafers to Replace Silicon in Electronic Devices

Silicon Carbide (SiC) wafers are increasingly found semiconductor devices that were once dominated by silicon. Researchers have found that SiC semiconductor devices advantages over silicon wafers based devices include:

  • Faster speed
  • Smaller stronger (Silicon Carbide is one of the strongest materials on earth.)
  • Greater efficiency in normal and adverse condition
  • Cost-effective in many applications.

Silicon Carbide can handle much higher temperatures and greater voltages than silicon semiconductors. This is great news for solar as SiC inverters are more robust. SiC can replace silicon in the following applications:

  • Solar Inverters and power electronic devices
  • Heat exchangers in solar concentrating power plants
  • Electric Vehicles (EVs)

    silicon carbide substrates

Which Silicon Carbide Wafer Can be Used to Make Sensitive van der Pauw sensor?

Researchers have used 50.8mm (0001) P-type 4H silicon carbide to fabricate van der Pauw strain sensor.

The van der Pauw sensor was fabricated with the followng SiC specs: 4° off-cut surface from the basal plane (0001) towards the 〈11[2 with combining macron]0〉 orientation. The 4H-SiC wafer has a thickness of 350 μm, wiht 1 μm p-type epilayer, 1 μm n-type buffer layer, and a low-doped n-type substrate. The p-type layer was formed using aluminum dopants, with a concentration of 1018 cm−3, while doping concentration of the n-type layer was also 1018 cm−3 with nitrogen dopants.

The following Specs Will Work For Your Research:

4H-SiC (0001) with 1 μm thick p-type epilayer with a concentration of 1018 cm−3" this P-type SiC epitaxial wafer

1> the wafer 3" to 6" diameter,but usually do 4" and 6"
2> thickness upon customer's requirement,as long as no less than 100nm
3> usually based on DSP SiC,SSP needs to do custom

What Silicon Carbide Wafer Specs Do Researchers Use?

Below is just an example of what specs university scientists need to conduct their research.

I am interested in purchasing a 6H SiC wafer, approximately 0.3-0.5mm thick, 2" diameter, high resistivity. It would ideally be double-side polished, but I would consider single-side. I am interested primarily in its optoelectronic properties, namely its bandgap energy and conduction band recombination time. Can you please send me details about the wafers you have in stock.

UniversityWafer provide the following:

6H SiC wafer, approximately 0.3-0.5mm thick, 2" diameter, Semi insulating type high resistivity >1E5 Ohm-cm, double-side polished, but I would consider single-side

2’’ SiC Specification_SI-type_2-6H-SI wafer
Material : High Purity Single Crystal Silicon Carbide
Polytype : Single-Crystal 6H
Orientation : On-axis<0001> +/-0.5 deg
Primary Flat : <11-20> +/-5 deg
Primary Flat length : 15.88 +/- 1.65 mm
Secondary Flat orientation : Si-face: 90° cw. from orientation flat +/-5°
Secondary Flat length : 8.0 +/- 1.65 mm
Diameter : 50.8 +/- 0.38 mm
Thickness : 330/430 +/- 25 um
TTV : </= 20 um WARP : </= 25 um
Si-face Surface & Roughness : CMP Epi-ready polish,Ra<0.5nm
C-face Surface & Roughness : Optical polished Ra<1nm or Fine ground
Dopant : V-Doped
Conduction Type : Semi insulating-type
Resistivity : >1E5 Ohm.cm
Micropipe Density : </= 30 micropipes/cm2
Laser Marking : Back Side @ C-face
Package : Neutral packaging,Single wafer box unless otherwise specified
Qty. 1pcs (Please contact us for pricing.)

Silicon Carbide Benefits Over Silicon

German automotive supplier Robert Bosch has taken a step to make electric vehicles more efficient and thus increase their range, Reuters reports. Tesla will use silicon carbide mosfets for its main inverter, according to a reverse engineering analysis by engineering firm Munro & Associates. [Sources: 11]

Compared to silicon, 650V silicon carbide mosses require less components and less energy than other inverters, such as lithium-ion batteries. They have a smaller footprint and a lower weight than silicon, for example, but require more power, more energy and less space in the inverter. [Sources: 3, 8]

In light of these limitations, we take a look at some of the benefits that silicon carbide power semiconductors, also known as SiC - mosfet, bring. Silicon carbide presents a challenge to silicon production, as silicon is more expensive to manufacture, which in turn presents a challenge for wider application due to cost increases. To generate more power from a very simple circuit, modules can incorporate multiple silicon carbide Mosfet chips into the same module, such as in a hybrid inverter or even an electric vehicle (EV). Silicon carbide and cascodes are a matter of course for hybrid devices, but represent a manufacturing problem compared to silicon due to their high costs. [Sources: 1, 12, 13, 14]

ST Microelectronics, ROHM Semiconductor and Infineon seem to be the technology leaders at the moment, but at Palmour we and others are working on how to optimize the modules to take full advantage of silicon carbide. Gallium nitride (GaN) devices provide photovoltaics while meeting the increasing energy demand. These technologies meet this demand from the specification point of view, but do not offer significant advantages over silicon. [Sources: 1, 7, 13, 15]

In addition, GaN has irregular clusters of carbon rings that interfere with electronic function, and this advantage is significantly impaired by the large number of connections between them. Even if the disturbing carbon clusters, which are only a few nanometres in size, can form, they can cause problems in the construction of silicon carbide. [Sources: 10]

The other main advantage (sic) is the high thermal conductivity of the silicon carbide and its high temperature. The temperature can be much higher than about 1,000 degrees Celsius, while silicon carbide can work at very high temperatures. As if that were not enough, silicone carbide parts can handle a variety of conditions, such as high pressure, low temperature, high humidity, etc. [Sources: 0, 1, 5]

To go a step further, the use of silicon carbide for energy conversion, which is often used in electronic systems, can increase the efficiency of solar systems. For example, a solar inverter can save 10 megawatts per gigawatt hour - and this is achieved by using this component instead of silicon, which represents considerable energy savings. Using a solar inverter, for example, can save 10 megawatts, while silicone carbides consume up to 10 gigawatts. [Sources: 3, 8]

For example, a solar inverter can save 10 megawatts per gigawatt hour, which represents a considerable energy saving. [Sources: 8]

One of the main advantages of this application is the high thermal conductivity of silicon carbide, which can dissipate frictional heat generated by friction at interfaces. The Solar Energy Technologies Office (SETO) supports research and development projects to promote the use of silicon carbide in solar inverters, solar photovoltaics and solar cells. Wolfspeed, named after its founder and CEO, Dr. David Wolf, is a professor of electrical engineering at the University of California, San Diego School of Engineering and a member of the MIT Department of Electrical Engineering and Computer Engineering. He was a key player in the development and implementation of a number of innovative technologies for the production of silicon carbonate and silicon carbide components and an example of why we were able to continue to play a leading role in this market. [Sources: 6, 8, 9]

The high bandgap requires a much stronger electric field to overcome this gap, and this makes silicon carbide much thinner than silicon components that can handle higher critical electric fields [sic], which further reduces resistance and power losses. [Sources: 2, 5]

In power electronics, semiconductors are based on silicon, and if the system voltage is below 1kV, the energy efficiency of silicon carbide would be much higher. If your system voltages are above 1Kv, this is very convincing, but in the long run it is not worth the cost. [Sources: 7, 10]

Power semiconductors manufactured with silicon carbide (SiC) have no such material limitation. In high-performance electronics, Si C has the ability to support the same energy efficiency as silicon MOSFETs, but at a much lower cost. [Sources: 2, 7]

Power semiconductors made of silicon carbide are capable of withstanding high temperatures, high pressure and high voltages, as well as high radiation levels. Compared to standard silicon, silicon carbide tolerates a much higher number of high and low pressure conditions. This means that even if you make a silicon MOSFET with a power semiconductor version the same size as the standard version, it will be blocked at higher temperatures by the silicon carbon fiber version. [Sources: 1, 4, 12]

 

 

Sources:

[0]: https://www.ppi-uk.com/news/silicon-carbide-sic-increasing-use-in-power-electronic-devices/

[1]: https://semiengineering.com/the-ins-and-outs-of-silicon-carbide/

[2]: https://www.designworldonline.com/can-silicon-carbide-deliver-on-promises-of-high-reliability-applications/

[3]: https://www.nacleanenergy.com/articles/38150/how-silicon-carbide-enables-sustainable-solar

[4]: https://thebossmagazine.com/silicon-carbide/

[5]: https://hackaday.com/2019/11/25/new-silicon-carbide-semiconductors-bring-ev-efficiency-gains/

[6]: https://www.azom.com/article.aspx?ArticleID=3271

[7]: https://www.eletimes.com/advantages-using-silicon-carbide-power-electronics

[8]: https://www.altenergymag.com/article/2020/05/how-silicon-carbide-is-changing-solar-power-systems/33171

[9]: https://www.energy.gov/eere/solar/silicon-carbide-solar-energy

[10]: https://phys.org/news/2019-09-silicon-semiconductor-carbide-efficient.html

[11]: https://www.futurecar.com/3528/Auto-Supplier-Bosch-to-Manufacture-Silicon-Carbide-Chips-That-Can-Extend-the-Range-of-EVs

[12]: https://www.euroscientist.com/what-are-the-benefits-of-silicon-carbide-in-semiconductors/

[13]: https://www.eetasia.com/st-intent-on-capturing-silicon-carbide-market/

[14]: https://eepower.com/technical-articles/sic-cascodes-and-their-advantages-in-power-electronic-applications/

[15]: https://www.azocleantech.com/article.aspx?ArticleID=789

Silicon Carbide to Drive Electric Motors

Silicon Carbide wafers are being used as wide bandgap devices that give engineers the ability to design efficient electric motor drives by reducing their size and getting closer to the motor. They can also switch quickly and have lower losses.

 

What you will learn:

SiC's benefits in detail

 

How to improve three-phase inverters for variable motor drive.

The rise of wide-bandgap (WBG), materials such as silicon carbide (SiC), and gallium-nitride(GaN) have been the most important advancement in power electronics over recent years. Wide Band Gap(WBG) materials promise smaller, more efficient, and faster power electronics.

WBG power products are already having an impact on a range of applications and topologies. They can be used for common power supplies, chargers, solar power, and energy storage. Silicon carbide, which is more commonly used in higher-voltage, high-power applications than GaN, has been on the market longer than GaN.

The motors represent a large portion of the total power used for industrial applications. They are used in HVAC, heavy-duty robots, material handling, and many other purposes. Cost reduction is possible by improving the reliability and efficiency of the motor drives. SiC is the choice of high-power industrial drive designers because of its unique properties.

SiC Material properties

Silicon carbide is a semiconductor metal with a greater bandgap (3.26 EV) than silicon (1.12 EV). It has many favorable properties for power electronics devices.

SiC has 10X more dielectric breakdown strength than silicon (Fig. 1). The ability to resist high voltages is one of the most important functions a power electronic switching device has. SiC has high dielectric strength and can support high voltages over a shorter distance. This distance also refers to the drift area between the drain contact and the channel in vertical devices. A device with a shorter drift zone will have lower electrical resistance and direct power losses.

1. SiC has many advantages. It offers a wider bandgap, such as a higher dielectric breakdown strength or better thermal support.

This wide-bandgap also decreases the number of thermally excited carriers. It results in lower free electrons as well as lower leakage current. Additionally, the leakage current remains stable and small over a wider temperature range than traditional Si devices. SiC MOSFETs/diodes make high-temperature applications more efficient.

SiC's thermal conductivity is 3X more than that of silicon, which allows for greater heat dissipation. The system design must include heat removal from power electronic devices. SiC's thermal conductivity makes it possible to reduce operating temperatures and thermal stress for the switches.

SiC is twice as fast as silicon in electron saturation velocity, making it possible to switch faster. A faster switch can operate at higher pulse-width–modulation (PWM), frequencies and has lower switching losses. Higher PWM frequencies can allow for smaller, lighter, cheaper passive elements in certain power-conversion topologies. These are often some of the most expensive and largest parts of the system.

Making SiC wafers is a more complicated process than making Si wafers. SiC boules can be pulled out of a melt but they must be grown inside a vacuum chamber using chemical vapor deposition. It takes a long time to grow and is difficult with acceptable defects. Silicon carbide is hard, brittle, and often used for industrial cutting. Special processes are needed to remove the boule from the wafer.

UniversityWafer, Inc., and partners maintain multiple SiC substrate channels to ensure that our research clients have enough capacity to meet their increasing SiC demands.

Improvement of Three-Phase Inverters

The three-phase inverter is the best option for variable-speed, high-voltage motor drives. It has silicon IGBTs and anti-parallel triodes. The inverter's three-phase coils are driven by the three-phase half-bridge phases. This produces a sinusoidal current waveform to the motor.

SiC can be used in many ways to increase the performance of this system. The energy lost to the inverter is made up of switching and conduction losses. SiC devices have the ability to influence both these loss mechanisms.

It's becoming more popular to replace the anti-parallel Silicon diode with a SiC Schottky Barrier diode. Si reverse diodes have a reverse recovery current that increases switching loss and generates EMI. SiC diodes offer a significant advantage. They have almost no reverse recovery current. This can reduce switching losses up to 30% and potentially lower the need to use EMI filters. The reverse-recovery voltage adds to the collector power at turn-on. A SiC diode decreases the peak current through IGBT, which increases system reliability.

Inverter efficiency can be further improved by replacing the IGBT with a SiCMOSFET (Fig. 2). SiC MOSFETs can reduce switching losses up to five times, further increasing efficiency. Based on the device selected, SiC MOSFETs' conduction losses can be as low as half those of Si IGBTs having the same current rating.

2. SiC MOSFETs, 650-V, are suitable for many high-performance applications such as the automotive industry.

This efficiency improvement results in less heat being wasted. Designers are now able to cut costs by either shrinking or eliminating active cooling. This allows the smaller motor drive to be mounted directly on the housing of the motor, shrinking the wiring and motor-drive cabinets.

WBG devices are fast and can switch between switches quickly. However, this reduces switching losses and creates other challenges. High dV/dt generates noise that can damage the motor-winding insulation. A gate resistor can be used to slow down switching, but the switching losses then rise back to the IGBT. Another option is to place a filter over the motor phases. As the PWM frequency increases, the filter size shrinks. This creates a tradeoff of heat and cost.

Fast switching power devices won't tolerate inductance or capacitance straying from the inverter circuit. Due to high switching transients, the so-called "parasitic” inductance could cause voltage spikes. You must ensure that your printed circuit board (PCB) layout is correct in order to eliminate parasitism. It is important to keep power loops and trace short and place devices close together. The gate-drive loop should also be kept short to minimize noise and the potential for unwanted device turn-on.

Power modules allow multiple devices to be integrated into the right topology for the motor drive (among other things). This results in a faster solution and low parasitic inductances. The power module helps to reduce PCB area as well as simplify thermal management by reducing heatsink parts.

 

Conclusion

These silicon-carbide device's fast switching speed and low losses make them an attractive option for efficient integrated motor drives. We have already discussed that system designers can shrink motor drive bodies and move them closer towards the motor to improve reliability and cost-efficiency. UniversityWafer, Inc’s provides the SiC substrates researchers need to help bring their plans to fruition.