Category | General Basics

High Frequency Inductive Heating

Posted on 06 February 2014

  Especially in the metal industry it is often necessary to heat objects, possibly for pouring, soldering, case hardening, melting or tempering of these parts. Mostly the heat is generated outside the object and via radiation or convection the heat is transferred to the object or work piece. A much more elegant method is to [...]

Basics of EMC and EMI

Posted on 27 December 2013

  Originally electronics was synonymous with telecommunications (radio, television, telephony). During operation these electronic devices often produced frequencies and harmonics which interfered with the correct operation of other equipment. These undesirable effects were known as RFI (RFI = radio frequency interference = high-frequency disturbance). Since the last few decades the number of electrical and electronic [...]

The Skin Effect

Posted on 25 September 2013

  If a DC current I flows through a conductor with diameter d, then the current density is J = \frac{4I}{\pi d^2} (A/mm2) and is constant throughout the cross-sectional area. In the case of an AC current this is not so. We can visualise this by imagining a conductor (fig. 1) as being composed of [...]

Hall Effect Sensors

Posted on 17 September 2013

  Hall effect If we place a current carrying conductor or semiconductor in a perpendicular magnetic field B (fig. 1) then an electric field arises perpendicular to the I-B surface. This effect is known as the Hall-effect. This effect was discovered in 1879 by the American physicist Edwin Herbert Hall. Figure 1. Hall effect Consider [...]

Opto-electronics

Posted on 04 September 2013

  LED (Light Emitting Diode) The light emitting diode (LED) has been used for years as a signal lamp, as number indicator and as a light emitting transmitter in an opto-coupler. In recent years the LED is becoming ever more popular as a light source. The operating principle of the LED rests on the release [...]

Sintering Technology

Posted on 17 April 2013

              Sintering combines two fine grained ceramic or metallic materials, usually under high pressure, at temperatures below the melting point of both materials. At a temperature of around 250°C, fine silver powder is sintered under high pressure to form a low-porous silver bond layer between the parts to be [...]

IGBT Characteristic Curve

Overload Behavior of Power Semiconductor Devices

Posted on 03 April 2013

    Power semiconductor device overload can be caused by excessive current or by excessive voltage. In both cases, possible destruction of the component is caused by (local) overheating of the silicon. Destruction of the elements can be prevented by appropriately limiting the duration of the overload.     Limiting Reverse Voltage using the Avalanche [...]

Solar Power System Control and Safety

Posted on 20 March 2013

  The Copenhagener climatic conference in 2009 and the earlier Kyoto protocol (adopted in 1997 and enforced as of 2005) committed different national governments to decrease their CO2 emissions. One of the possible ways to achieve these goals is to increase the production of sustainable energy and to issue a grant for every initiative taken. [...]

Masking and Structuring Silicon

Posted on 26 February 2013

                    Masked Diffusion When producing semiconductor devices, it is necessary to limit the areas that the dopant used is able to penetrate. In order for the dopant to penetrate into the silicon at given locations, the silicon surface is covered using a mask, usually composed of [...]

ion radiation

Charge Carrier Lifetime in Semiconductors

Posted on 11 February 2013

              Charge carrier lifetime refers to the average time taken for a minority charge carrier (electron or hole) to recombine with one of its counterparts (with opposite charge). The ability to calibrate charge carrier lifetime in semiconductors provides a means of controlling certain properties when producing power semiconductor devices. [...]