Monthly Archives: April 2016

Can Hardware Thwart Attackers?

At the Gamecon Congress 2015 at Cologne, Germany, Intel announced its 6th Generation of Core processors. Although they did not elaborate, the new chips have vPro on-chip hardware, which is important to the security of business users. Among the new 6th Generation vPro Cores, several of them have new hardware capabilities that include Authenticate and Unite. Intel claims this on-chip hardware to be unhackable, and these can verify the identity of users, allowing them to project their screens onto any WiDi or Wireless Display in the world.

According to Tom Garrison, General Manager of Intel Business Client, the 6th generation vPro Cores will offer workplaces higher productivity, higher security, and higher collaborative experience for business users. As more enterprises now allow users to choose their own devices ranging from Windows to Apple products, Intel is targeting at lowering the price of transforming the workplace in accommodating them. For instance, Intel claims to have dropped their workplace cost per user from $250 to $150 through the transformation.

Intel 6th Gen vPro users now have three-way docking – with their WiDi, WiGig or their business network. They can also use the wired Thunderbolt dock as it has a dual function, charging the laptop and offering 40-Gbit speeds. Intel claims 300 design wins for their 6th generation design WiDi capabilities and about 600 for the WiGig.

According to Intel, with their 6th Gen vPro cores, users will see several improvements, even in the five-year old laptops that several businesses still use. These include a 2.5-fold performance improvement, three times extension of battery life, and 30-times speedier graphics performance. Intel is also offering its mobile users a performance equivalent to Xeon-caliber. However, the most important announcement still remains the authentication hardware from Intel.

According to Garrison, Authentication is a new capability, never before seen. Using Authentication, the information technology department of a business can guarantee the authenticity of any user with two or more factors. That makes break-ins using stolen credentials virtually outdated.

With Authentication, users can select up to four additional factors supported by the unhackable on-chip hardware. This includes PIN, proximity of the phone using Bluetooth, a defined location such as the office, home, or any other, and biometrics such as retina scan or fingerprint.

With Intel Unite hardware, the 6th Gen Core processors allow business users to link their laptop screens wirelessly onto any connected display in the world. They can also control their environment such as dim the lighting and other niceties. Users have to enter a six-digit PIN to connect to any WiDi equipped display, whether in a conference room or anywhere in the world. For business users, this comes complete with Skype. Now, the 6th Generation core users can mirror their laptop display on any big screen-presentation without having to turn to dongles, cords, or wires.

Even in this down market, Intel is claiming 200 business-wins for its 6th Gen vPro Cores, along with 100 vPro design-ins, and over 30 wins with their Intel Ultrabook designs. They have also completed 300 trials of deployment for their WiDi wireless display technology, and more than 600 trials with their WiGig wireless docking design-wins.

What is the MHL Specification?

A present, we are inundated with a plethora of digital devices. For example, we have set-top boxes or STBs, Blu-ray players, AVRs, automobile information systems, monitors, TVs, tablets, smartphones and others making up this large and diverse ecosystem. For getting all these to plug-and-play together is no mean feat and the latest standard connector that manufacturers are adopting for compatibility is the USB Type-C.

The protocol that the USB Type-C will be using for the delivery of audio, video, data and power is the MHL Alt Mode for the superMHL and MHL 1, 2 and 3 specifications. MHL Alt Mode over USB Type-C will allow interconnections of more than 750 million MHL devices. With USB Type-C, you can never plug-in a device in the wrong way – this is a reversible connector.

Backward compatible with USB 2.0 and USB 3.1, both Gen 1 and Gen 2, MHL Alt Mode for USB Type-C features power charging and Immersive audio such as DTS:X, Dolby Digital, Dolby Atmos and more. It allows transmission of 4K data at 60fps over a single lane or 8K data at 60fps over 4 lanes. You can use your existing remote to control existing MHL phones, as there is backward compatibility with existing MHL specifications.

The MHL Consortium has developed and published the MHL Alternate Mode for the superMHL and MHL 1, 2 and 3 specifications. They have established a liaison with the USB-IF and USB 3.0 Promotion Group for obtaining the official SVID and for ensuring the development of the specification confirms to USB Type-C, USB Billboard and USB Power Delivery specifications.

MHL Alt Mode over USB Type-C presents a single, small form factor connector, an ideal for many devices for delivering audio, video, data and power. You can simultaneously charge your smartphone, tablet or notebook when you connect them with larger displays such as car information systems, projectors, monitors and TVs
.
You will know your USB Type-C port on your host and device supports MHL if you see the USB-IF logo near the port. Smartphones and tablets with the MHL Alt Mode can easily connect to existing car infotainment systems, projectors, monitors and TVs. With MHL cables and MHL-to-HDMI adapters supporting USB Type-C, you can connect to HDMI Type A devices as well. For this, you will need a simple, thin MHL cable that has an HDMI Type A connector on one end and a USB Type-C connector on the other.

A user can use his existing TV remote to control the device as the MHL Alt Mode supports Remote Control Protocol as well. In contrast, an alternative technology DisplayPort from MPEG-LA does not offer the same compatibility. With the DisplayPort Alt Mode, the user would have to actually go to the connected device and manually control it.

Protocol adapters for the DisplayPort Alt Mode will not work for the MHL Alt Mode and vice-versa. Manufacturers will have to use proper labeling to identify DP Alt Mode or MHL Alt Mode on adapters to avoid consumers from being confused. Proper protocol adapters are necessary for the MHL Alt Mode to support VGA, DVI and HDMI displays.

What is Biometrics?

Many areas are seeing the spread of biometrics. These include military electronics, law enforcement, border protection, industrial and business security, medical devices, consumer electronics and financial transactions. The most important reasons for the rising interest in biometrics comes from the forced emphasis on safety and security because of increasing instances of terrorism, fraud and identity theft.

Biometrics technology is poised for sustained growth. This is also evident from the figures in the recent market research report released by Acuity Market Intelligence. According to this report by Frost and Sullivan, the compounded annual growth rate or CAGR of biometrics technology is expected to be nearly 10.69%, with the annual market revenue reaching $11 billion by 2017.

According to the report, biometric technology earned about $300 million in 2008 in countries such as Africa, the Middle East and in Europe. The report expects this market to reach about $1.5 billion by 2015, representing a CAGR or 25.5%. Similarly, the forecast for North American revenue in biometrics is $9.44 billion.

A major factor in this growth has been Government projects worldwide such as the national identity schemes and e-passports. The biometrics industry continues to lay their emphasis on practical and low-cost standardized approaches for ensuring user friendliness, non-invasiveness and optimal security.

Biometrics employs various modalities for personal identification and verification techniques, with each providing different levels of authenticity. These include signature recognition, voice recognition, vein and palm recognition, hand recognition, facial feature recognition and fingerprinting. A recent addition, the holographic method, has gained popularity. Along with personal data on databases, any of the above modalities can improve authentication and identification greatly.

The public identifies fingerprinting as the most common technique related to biometrics, followed by iris recognition. With improved optical sensing, thermal and capacitive technologies, fingerprinting is improving on several fronts.

For example, NIST or the National Institute of Standards and Technology are promoting a new software technology, the AFEM or Automated Feature Extraction and Matching. This speeds up the manual portion of latent fingerprint identification.

Under normal conditions, a fingerprint examiner has to mark carefully the distinguishing features of a partial or full latent print. This begins with the positions where ridges branch or end. Further identification proceeds when he enters the print into the FBI’s IAFIS or Integrated Automated Fingerprint Identification System.

Trial of the AFEM system on a data set of 835 latent prints and 100,000 fingerprints has shown promising results. Used in real case examinations, the AFEM system demonstrated high accuracy for the latent prints and fingerprints, as high as 80% for half the prototypes.

For each latent print, the software filtered out the distinguishing features and compared them against the 100,000 fingerprints. Against each print, the software was able to provide a list of 50 probable candidates. When specialists compared the fingerprints by hand, they were able to find identities within the top 10.

NIST researchers are working closely with the law-enforcing agencies such as FBI to develop a mobile ID platform. This will allow fingerprinting on the spot, eliminating the need for law-enforcement officials to take people to headquarters for fingerprinting.

How to Safely Grab an Ant

Any child can confirm that ants are not delicate creatures. Their size makes it difficult for us to grab an ant without harming it. Unless you happen to be an Entomologist, wrangling with an ant may not fall into your general activities. However, if for some reason you have to pick or hold something as small or smaller, a micro-tentacle would be the best way to go.

Traditional tweezers are no good when grasping tiny delicate objects such as blood vessels. The process can be painstaking as putting a little too much pressure might crush the object – deciding how much pressure is adequate may also be difficult to gage.

At the Iowa State University, scientists have developed a micro-tentacle or a miniature coiling tentacle, which is just suited for holding tiny objects such as an ant, without causing it any harm. According to the researchers, such micro-scale soft-robots hold a lot of promise as safe handlers for delicate micro-objects. However, to adopt them for wider applications requires easily fabricated micro-actuators of great efficiency.

The micro-actuator for the miniature coiling tentacle developed by the researchers at the Iowa State University is actually a pneumatic actuator based on an elastomeric micro-tube. It is a highly deformable, long and thin micro-tube, based on a new technique called direct peeling. While building the semi-analytical model for shape engineering, scientists use them in combination, amplifying the pneumatically driven bending of the micro-tube into inward spiraling multi-turns.

The result is a micro-tentacle with a grabbing force of nearly 0.78 mN and a final radius as small as 185 µm. That makes it ideally suitable for non-damaging manipulations capable of handling fragile micro-objects. With this spiraling micro-tentacle based grabbing modality, scientists have given the field of soft-robotics several new concepts such as direct peeling, micro-tube shape engineering and the elastomeric micro-tube fabrication technique.

Applications such as vivo biomedical manipulations are increasingly turning to elastomer-based soft-robots for handling delicate objects. Although a lot of headway has been achieved for their micro-scale miniaturization, finding suitable and efficient actuators has remained a difficult task so far. Tentacle actuators composed of polydimethylsiloxane or PDMS elastomers are the answer.

Researchers dip a rod-shaped cylindrical template in a bath containing liquid PDMS. The PDMS clings to the template as researchers pull it out of the bath. They leave the PDMS-coated template in a horizontal position for curing. Most of the gelling elastomer collects on the underside of the template, because gravity pulls it down. That makes the coating on the top much thinner than at the bottom.

When the PDMS sets to a soft and rubbery consistency, it is peeled off the template. That results in a hollow micro-tube, with an uneven wall that is thicker on one side and thinner on the other. Scientists then plug one end of the tube. When they pump air in through the other end, the tube as a whole coils towards on its thinner side and the higher air pressure makes it stiffen. For accentuating the coil formation, scientists add a lump of PDMS to the base of the micro-tube on the outside of the thinner side.

Driving Steppers with the RasPiRobot Board

The Raspberry Pi or RBPi is an inexpensive, tiny single board computer running the Linux operating system. As such, the standalone RBPi is not suitable for running motors, but when combined with an expansion board such as the RasPiRobot Board, you can easily run DC motors as well as Stepper motors off the RBPi. For this, you must use the version 2 of the RasPiRobot or RRBv2 board. Please note you can run only 5V steppers with the RBPi RRBv2 combination, as this board does not support 12V motors.
In practice, the RRBv2 board sits over the RBPi fitting over the latter’s GPIO connector. The stepper motor wires connect to the RRBv2 board, using its L & R screw terminals. To do that, you must first strip the wire ends of their PVC insulation, until about 10 mm of bare copper wire is exposed. Unscrew the terminal sufficiently to allow insertion of the copper part of the wire into the hole. Turn the screw clockwise to let the jaws hold the wire firmly.
One of the advantages of using the RRBv2 board is you can run the stepper motors from a battery pack. The board has a switch-mode power circuit to provide stable power to the motors. Additionally, you can even run your RBPi from this on-board power supply. That makes the entire arrangement completely portable.
When connecting the battery pack to the RRBv2 Board, take care to observe the correct polarity of the flying leads from the battery pack. Some battery packs terminate the wires on a plug. Therefore, you must use a matching female socket adapter that has flying leads. In either case, connect the positive or red lead to the screw terminal marked Vin on the RRBv2 board. Connect the negative or black lead to the screw terminal marked as GND on the RRBv2 board. Powering on/off through a battery pack becomes simpler if there is a built-in switch.
If you have connected your RBPi to the RRBv2 board, throwing the switch to the on position will allow the RBPi to start booting. To run the stepper motor with commands from the RBPi, you will need to download the RRBv2 Python library codes. For this, you will have to connect your RBPi to the Internet.
You can use the Ethernet connection to connect your RBPi to the Internet. Alternately, you may use a suitable Wi-Fi dongle. Once online, use SSH to establish connection to the RBPi from a PC and proceed to download the RRBv2 Python library from here and install it.
To run a stepper motor, you can write some simple Python codes, following the tutorial here. For example, you will have to provide the delay between the steps, the total number of steps you want the stepper motor to move and the direction of rotation – backwards or forwards.
The delay between the steps governs the speed of rotation of the stepper motor. For example, as you make the steps larger, the motor turns more slowly to make the total number of steps.

Room Automation and Raspberry Pi

Most people prefer to come back to a cozy room after a full day’s work. For many, this may not always be possible, unless someone turns on the AC at the right time. For those living alone, help is available in the form of a single board computer, the Raspberry Pi or the RBPi. In addition, the RBPi operates the blinds and you can control it from anywhere in the world – the RBPi is connected to the Internet.

For this project, you will need an RBPi with a suitable SD card, a Wi-Fi dongle, a stepper motor. You will also need a power source capable of driving the RBPi and the motor, a stepper motor driver board, an IR receiver, an IR LED and an NPN transistor.

Controlling the AC is a simple affair, with the RBPi simulating the infrared information the remote control normally uses. You need to use the LIRC library for the RBPi to record this IR information via the IR receiver. The infrared LED driven through the NPN transistor duplicates the signal sent by the remote control of the AC. Initially, you must let RBPi learn the IR codes by recording those using commands in the LIRC library. LIRC produces a configuration file that holds the IR codes for your AC. Playing back these codes through the IR LED allows you to control the AC just as its own remote does.

The RBPi and the motor driver board control a stepper motor for driving the blinds. The RBPi merely drives a GPIO pin to let the motor driver board know if it must operate the stepper. The driver board already has the necessary parameters stored within it for driving the motor. By default, the motor remains off so that it does not waste power when it is not needed. The software takes care of this by turning off the Enable pin on the stepper driver board. When you need to operate the blinds, a script on the RBPi turns the GPIO pin on and off.

To operate the unit from remote, you need to connect the RBPi to the Internet via a wireless network. Use the Wi-Fi dongle for this, configuring the RBPi to switch on the wireless connection immediately after booting. Web access to the stepper motor controller is through Nginx and PHP.

The entire setup works when the RBPi connects wirelessly to the network. You access a web interface and use it to send commands to the controller script running on the RBPi. Depending on the commands sent, you can access either the blind opener or the AC control. For opening the blinds, the RBPi sends on or off signals to the stepper motor controller board.

On the other hand, the RBPi sends the appropriate commands to the air conditioner via the IR link. Depending on the code transmitted over the IR link, the AC will switch either on or off. Additionally, with proper codes transmitted from the RBPi to your AC, you can even set the temperature of the room before returning at the end of the day.

Drive a 16-Channel Servo with the Raspberry Pi

To drive servomotors micro-controllers must have PWM outputs. These are output pins on which the micro-controller will generate pulse outputs with controlled or modulated variable widths. Most embedded micro-controller units have one or more of these outputs. The famous single board computer, the tiny credit card sized Raspberry Pi or RBPi also has one IO pin dedicated for PWM. This is the PWM channel available at the GPIO18 of the RBPi and with this, you can drive a single servo at best. However, if you want the RBPi to drive more than one servo, it will need additional circuitry.

A PWM driver IC such as the PCA9685 can drive 16 servos at a time, but requires commands and data through its I2C interface. Fortunately, the RBPi can also communicate using the I2C protocol, enabling it to control 16 servos via the PCA9685. Adafruit has a very convenient breakout board with the PCA9685 on it and that makes it very convenient to connect to the RBPi. Not only can you drive servos with the PWM outputs, you can use the PWMs for controlling LED lighting as well.

To let RBPi communicate with the I2C protocol, it will require a special OS available from Adafruit. This is the Occidentalis flavor and it has all the libraries required for invoking I2C. However, if you are using the stock Raspbian OS, you must install the python-smbus and the i2c-tools using the “sudo apt-get install” command. To learn more about using I2C, refer Adafruit’s rather informative tutorial.

The two packages will allow you to search for any I2C device connected to the RBPi. The easiest way you can connect the servo breakout board to your RBPi is with the help of the Adafruit Pi Cobbler. Here, VCC is the digital supply for the IC or 3.3V, and V+ is the supply for the servomotors (typically 5V).

The actual chip that drives the servos, the PCA9685, needs 3.3V, and connects to the VCC on the cobbler board. Servos usually require much higher currents to operate. Therefore, they are powered from a separate power supply, typically 5V, and are connected to the V+ on the Cobbler. Note that this 5V is different from the 5V supply for the RBPi. The PWM operation on the servos creates a huge amount of electrical noise, which can cause the 5V supply voltage to fluctuate significantly. RBPi may not be able to tolerate such voltage fluctuations, and this may cause it to crash and lock up.

If you are driving many servos, it will be a good idea to add a capacitor to the driver board. There is a spot already marked for such a capacitor. As a thumb rule, you need a capacitor with a value n x 100uF, where n is the number of servos you are driving. Capacitors are manufactured in standard ratings, and you may have to go for the next higher standard value that you have calculated.

Depending on whether you are using a standard or continuous rotation servo, your python code will vary. For the actual code with which you can control the various parameters of I2C and hence the servo, you may refer to this site.

Here Comes the Raspberry Pi 3

The world woke up to a 256MB Raspberry Pi, or RBPi, Model B on 29 February 2012, and found it fascinating enough to order over eight million pieces since that date. That has made the Raspberry Pi Foundation of UK grow from a few volunteers to over sixty full-time employees, and the RBPi 2 an all-time best-selling SBC or single board computer.

In celebration of their fourth birthday, the Raspberry Pi Foundation has released their new model of the RBPi, keeping the price same as that for the existing RBPi 2. The new RBPi 3 offers over 10 times the performance of the RBPi 1, and comes with an integrated Bluetooth and wireless LAN, while keeping complete compatibility with the RBPi 1 & 2.

RBPi 3 Model B, as the new RBPi is called, features the BCM2837 SoC, belonging to the same family of Broadcom processors as its predecessors. That means all the projects and tutorials you relied on for the precise details of the RBPi hardware so far, will continue to work for the RBPi 3 as well.

RBPi 3 comes with a new ARM Cortex-A53, quad-core processor, custom-hardened and running at 1.2GHz. Along with various architectural enhancements, including a 33% increase in the clock speed, the new SBC offers a 50-60% increase in performance, when operating in 32-bit mode, over its immediate predecessor, the RBPi 2. Compared to the original RBPi, the new RBPi 3 gives nearly a ten-fold improvement in performance.

Designing the RBPi 3 with the BCM2837 was not a simple task, as it also contains the BCM3438 wireless combo chip, while it retains the same form factor as that of the RBPi 2 Model B. However, the designers have done it, with only the position of the LEDs changing to the other side of the SD card socket to allow the antenna to be positioned. Running an extensive and expensive wireless conformance campaign has allowed the Raspberry Pi Foundation launch the RBPi 3 in almost all countries simultaneously.

As all the connectors are in the same place, with the same functionality, you can house the RBPi 3 in the same enclosure that you had been using for the RBPi 2. Although the board still runs from the same 5V, 2A adapter via the micro-USB connector, it is recommended to upgrade to a 5V, 2.5A adapter if you are connecting power-hungry USB devices to the RBPi 3.

You will need an updated operating system – a Raspbian or NOOBS image – to take advantage of the functions of the new board. Although the new image remains 32-bit for the time being, there is likely to be a shift towards a 64-bit image after a few months. There is also a plan for an RBPi 3 Model A, with the form factor of the RBPi Model A+.

Industrial customers who want to stick with the RBPi 1 or RBPi 2, including Models B and B+, can do so because these models will be continued for as long as there is a demand for them. Additionally, VideoCore IV 3D will continue to be the 3D graphics core for all RBPi models.

Is the Odroid SBC Better than Raspberry Pi 3?

The world of inexpensive SBCs or single board computers has been taken by a storm with the unveiling of the new Raspberry Pi board or the RBPi 3. The claim being it blows the competition away, and that no one can match its price. However, that may not be entirely true, as the Odroid C2 SBC seems to best the RBPi 3.

Hardkernel promotes its Odroid C2 as another cheap and speedy SBC with a 64-bit ARM-based quad core processor. A comparison of the specifications shows the C2 may be giving the RBPi 3 a run for its money. Compare for instance, the BCM2837 of the RBPi 3 with the Amlogic S905 SoC of the C2. Although both are quad-core ARM Cortex-A53, the C2’s processor runs at 2GHz to the 1.2GHz of the RBPi 3. At 2GB, the C2 has double the RAM of the RBPi 3, which has only 1GB. Moreover, the C2 comes with a Mali-450 GPU, able to deliver 4K video.

Although the C2 does not have the on-board wireless and Bluetooth features of the RBPi 3, it has a high-speed Gigabit Ethernet port directly wired into the SoC. The RBPi 3 also has Ethernet on-board, but as this is a 100-megabit port and is on a USB interface, its speed is likely to be limited.
The two boards share a very similar form factor and are nearly identical in their GPIO capabilities. In addition, for both the boards, you can choose the storage to be either the usual micro SD card or eMMC. However, it is worth stating that the C2 comes with a built-in ADC or analog to digital converter. When it comes to operating systems, the C2 can operate with Ubuntu 16.04, or Android lollipop.

The RBPi family, just like Apple products, has always faced competition. However, most look good only on paper, but their prices always let them down in the end, and we never hear of them after some time. The price of $40 for the C2, being very close to that of the RBPi 3, may just escape this fate. Of course, there is the matter of adding shipping and customs to the price, as the origin of C2 is Korea.

So, which of them is preferable – the C2, or the RBPi 3 – and why? The faster processor of the C2 and its faster wired networking would make it attractive to someone working on network-attached data processing applications. Although one can add a USB wireless network adapter for only a few dollars, the onboard Wi-Fi and Bluetooth of the RBPi 3 makes it so much more attractive. Therefore, the RBPi 3 would be coveted by anyone who is a home user or planning to use a computer on a platform that will remain unfettered by wires.

Although the C2 may be more impressive when compared to the RBPi 3, the latter will likely outsell the C2 many times over. This may not be because of the massive publicity advantage that the RBPi 3 is receiving from the Pi foundation, but more likely due to the wide ecosystem of hardware and software developers the RBPi family has at present.

New Combination of Materials for Efficient Solar Cells

An international team of scientists have come together to build solar cells with high efficiency using a new blend of materials. The materials used allow the cells to convert sunlight into electrical energy without the addition of dopants. The design, termed DASH, uses molybdenum oxide and lithium fluoride.

Doing away with doping

Most of the solar cells use silicon wafers in the crystalline form. The wafer, along with the layers of materials deposited on it are doped or injected with special impurity atoms that either introduce free electrons or create electron deficiencies called holes. The presence of these extra electrons or holes increases the electrical conductivity of the material. However, the impurities introduce certain complexities within the crystalline structure, which bring down the performance.

Since solar cells are all about increasing the performance of these devices, researchers have been looking at means to eliminate the doping process. The international team has made available a cell prototype with a simple architecture. The journal Nature Energy has published an article on the design of the solar cell. James Bullock, a faculty member of Australian National University and a team member is the principal author of the paper. He has been a visiting researcher at Lawrence Berkeley National Laboratory and UC Berkeley as a part of the project.

Bullock explains that the simple structure of the cell designed by them would cut down the production and operational costs considerably, thereby enhancing the efficiency. The silicon cell, free from doping impurities designed by the team is termed DASH, which is the acronym for dopant-free asymmetric heterocontact. The efficiency of this product is 19%, which exceeds that of other dopant-free cells. The efficiency of previous cells of this category did not exceed 14%.

Special properties of the contact materials

The researchers applied several layers of amorphous silicon over a wafer of crystalline silicon. This was overlaid with very thin films of molybdenum oxide on the sun exposed surface and lithium fluoride at the bottom one. These two external layers are only a few nanometers thick and act as contacts for the holes and electrons. Ali Javey, a team member and a professor of Electrical Engineering and Computer Science at UC, Berkeley, explains that both molybdenum oxide and lithium fluoride have been selected for making up the contacts because of their special properties. The materials form transparent layers at this thickness. Molybdenum oxide has several imperfections in its crystalline structure that allow it to act as an effective hole contact.

Likewise, the defects in the lithium fluoride structure allow it to be a useful electron contact. Stefaan de Wolf, another team member has described in the article how the molybdenum oxide and lithium fluoride layers work as effective contacts when used with a combination of amorphous and crystalline silicon. In addition, these materials have allowed the scientists to come up with remarkable variations in their properties with different thicknesses.

The scientists used the thermal evaporation technique at room temperatures to apply the coatings. Javey said that the researchers intend to use the material combination for other semiconductor applications like transistors to improve their performance.