Our company TÜRCERT can conduct ESD Electrostatic Discharge tests in its own laboratories during EMC tests in accordance with IEC / EN standards or as ESD tests only.

Electrostatic Discharge (ESD) is a sudden electric current, short circuit or dielectric breakdown caused by the contact of two electrically charged objects. The increase in static electricity can be caused by friction loading or electrostatic induction. ESD occurs when two differently charged objects are brought together or dielectric breaks between them, often creating a visible spark.

ESD can create extraordinary sparks (lightning is a major ESD event with thunder accompanied by thunder) or less pronounced shapes, which are still quite sufficient to damage sensitive electronic devices. Electrical sparks require field strength in the air above about 4 kV / cm, as in lightning. Other forms of ESD are the discharge of sharp electrodes by corona discharge and non-sharp electrodes by leakage.

ESD can cause some of the major harmful effects in the industry (including gas, steam fuels, coal dust explosions, and failure of certain components of solid state electronics, such as integrated circuits). They may suffer permanent damage when exposed to high voltage. Electronics manufacturers have therefore identified electrostatic protection areas without static electricity by taking precautionary measures (avoiding high electrically charged materials and providing earth-gathering means for human employees, providing current-collecting means, controlling humidity, and taking measures to eliminate static electricity).

ESD simulators can be used to try out electronic tools. (For example, model of human body with electrically charged vehicle)

Electrical discharge can occur in the 2 way. The other way is contact discharge. The discharge can find its own path in the air and jump anywhere on the device. In order for the discharge to occur through contact, the metal surface must be touched and the discharge occurs at the point of contact. Therefore, the most important thing to remember and remember in an ESD test environment should be to hold the object under test and approach too much.

Causes
One reason for ESD is static electricity. Static electricity is usually caused by friction loading (the electrostatic charge distribution by contacting and then separating the two substances). Walking on the carpet, rubbing a plastic comb on dry hair, rubbing a balloon in a sweater, rising in the fabric seat of a car, or removing some plastic packages are examples of frictional electrification.

Another cause of ESD damage is electrostatic induction. Electrostatic induction occurs when an electrically charged object is placed next to a conductive material separated from the ground. The presence of the charged object creates an electrostatic field which causes the redistribution of electrical charges on the surface of the other object. Although the total electrostatic charge of the object does not change, it now has over-positive and negative charge regions. An ESD event may occur when the object contacts the conductive path. For example, the charged areas on the surface of the styrofoam cup or bag can induce potential in ESD sensitive components by electrostatic induction, and if this component is brought into contact with a metallic device, an ESD event may occur.

formats
The most extraordinary form of ESD is the spark generated by a strong electric field creating an ionized conductive channel in the air. This can cause minor discomfort to people, severe damage to electronic equipment, and fires and explosions if the air contains combustible gases and particles.

But most ESD events occur without invisible and inaudible sparks. A person with a relatively small electrical charge may not be able to feel sufficient discharge to damage a sensitive electronic component. Some vehicles can be damaged with a small discharge as small as 30V. These invisible forms of ESD can directly lead to electronic vehicle disturbances or less pronounced forms of loss of efficiency in vehicles' long-term reliability and performance. The deterioration of some vehicles may not be obvious during the service period.

sparks
Main article: electric sparks
The spark is triggered when the electric field strength exceeds approximately 4-30kV / cm (dielectric field strength of air). This phenomenon may cause a sudden increase in the number of free electrons and ions in the air, causing the air to suddenly become an electrical conductor in the process called dielectric degradation.

Probably the best-known example of natural spark is lightning. In this case, the electrical potential between the cloud and the ground or between the two clouds is often up to hundreds of millions of volts. As a result, the current flowing through the travel channel causes a huge energy transfer. On a much smaller scale, sparks can occur as low-charged objects as 380 V during electrostatic discharges in the air. (Paschen's law) The Earth's atmosphere consists of% 21 oxygen (O2) and% 78 nitrogen (N2). During an electrostatic discharge, such as a flash, the affected atmospheric molecules are electrically stretched. The diatomic oxygen molecules are separated. They are in the form of ozone (O3) which is unstable or reacts with metals and organic substances. If the electrical voltage is high enough, nitrogen oxides (NOx) may form. Both products are toxic to animals and nitrogen oxides are required for nitrogen fixation. Ozone adheres to all organic substances with ozone decomposition and is used in water treatment.

Sparks are a source of combustion for highly flammable environments and can cause devastating explosions in these dense fuel environments. Most bursts occur after a very small electrostatic discharge, regardless of whether there is an unexpected fuel leak that invades a known open-air spark device or an unexpected spark in a known fuel-rich environment. If oxygen is present and the three conditions of the fire triangle are combined, the result is the same.

Damage prevention in electronics

Part of the static unloader of a spacecraft.
Many electronic components, especially microchips, can be damaged by the ESD. Precision components; it needs to be protected during and after manufacture, during transportation and assembly of parts and in the finished state.

Protection during manufacturing
Prevention of ESD in manufacturing is based on the Electrostatic Discharge Protected Area (EPA). The EPA can be a small working area or a large manufacturing area. The basic principle of the EPA is to avoid the presence of highly charged materials in the vicinity of ESD-sensitive electronics. All conductive materials and workers are grounded and load accumulation is prevented in ESD sensitive electronics. International standards specify a typical EPA, which is found by examples such as the International Electrotechnical Commission (IEC) or the American National Standards Institute (ANSI).

ESD prevention in EPA; the use of appropriate ESD safe packaged materials, the use of conductive thin yarns in the garments worn by employees, the use of conductive wrists and foot clamps to prevent high voltage build-up in employees' bodies, the use of anti-static carpets or conductive flooring materials to keep harmful electrical load away from the work area, and moisture content. control. Since the thin layer of moisture accumulated on most surfaces serves to dissipate electrical charges, damp conditions prevent the formation of electrostatic charges.

Ion generators are sometimes used to inject ions into the air stream of the medium. Ionization systems help neutralize the charged surface regions of insulators or dielectric materials. Conductive materials prone to electrification by friction should be kept away from sensitive devices to prevent accidental charging due to induction. In aircraft, static unloaders are used at the end edges of wings and other surfaces.

Manufacturers and users of combined circuits should take a number of measures to avoid ESD. ESD prevention may be part of the device itself or may include specific design techniques for the input and output terminals. External protection components can also be used with the design of the circuit.

Due to the dielectric nature of the electronic components and tools, electrostatic charging cannot be completely prevented during the management of the devices. The manufacturing and management of most ESD-sensitive electronic tools and components is so small that it can be finished with automated equipment. ESD prevention processes are therefore very important with these processes in which the components are brought into direct contact with the hardware surfaces. It is also important to prevent ESD as soon as the components sensitive to electrostatic discharge come into contact with other conductive parts of the product itself. The most effective way to prevent ESD is to use materials that are not very conductive but can slowly remove the static charge. These materials are called static distributors and have resistances in the range of 105 to 1012 ohm-meters. In automated manufacturing, materials that touch the conductive areas of ESD-sensitive electronics must be made of dispersing material and must be grounded.

Protection during transport
Sensitive devices must be protected during transport, use and storage. The increase and discharge of static can be minimized by controlling the surface resistance of the packaging materials and the resistivity volume. The packaging process is also designed to minimize the friction electrification of the packages during transport, which may be necessary for the packaging material to contain electrostatic or electromagnetic protection.

Simulation and testing for electronic devices

Electric discharge
An ESD simulator, often called a human body model (HBM) with a special output circuit, is often used to test the sensitivity of electronic devices to ESD, which may result from human contact. It consists of a capacitor connected in series with the resistor. The capacitor is charged to a certain high voltage by an external source and the load is suddenly discharged via the resistor to the ends of the device under test (DUT). The most widely used JEDEC 22-A114-B standards (100 pico farad capacitor and 1500 ohm resistance is specified as). MIL-STD-883 Method 3015 and ESD Association's ESD STM5.1 are other similar standards. IEC / EN 61000-4-2 test specifications are used to comply with the standards of the European Union of Information Technology Equipment (EU, Europoean Union). To measure the stability of the product; guidelines and requirements for test unit geometries, manufacturer specifications, test levels, discharge rate and waveforms, forms and points of discharge in the deki victim ”product, and operational criteria.

The loaded device model (CDM, Charged device model) test is used to determine the ESD to which the device can resist when the device has its own electrostatic charge and is discharged due to metal contact. This form of discharge is the most common form of ESD in electronic devices and causes most ESD damages during manufacturing. The CDM discharge is mainly dependent on the interference parameters of the discharge and the size and shape of the packaging component. One of the most widely used CDM simulation test models has been identified by JEDEC.

Other standardized ESD test circuits are the machine model (MM, Machine model) and transmission line vibration (TLP).

ESD Abbreviation for electrostatic discharge (discharge). Static electricity discharges are a series of physical events that we can experience every day. Static loads; it can occur on conductive and non-conductive materials or on humans. The human body is a resistance as well as a capacitor. People; friction during walking, getting in and out of vehicles, working at the table, wearing clothes and so on. during daily activities such as (+) or (-) are charged with electric charge. While shaking hands in daily life, touching the door handle gives a feeling of distortion. All these formations are discharge of electrostatic charge accumulated on human.
We do not realize the discharge (discharge) in our daily life. Because; It is necessary to discharge more than 3000 Volts to feel, 5000 Volts to see and 10.000 Volts discharge to see.
While the developments in the electronics industry continue rapidly, it brings many problems together. The most important of these problems is ESD. The damage caused by ESD is not at all underestimated. It has been determined that these damages are caused by% 25 in electronic materials and% 50 in working devices. Considering that the cost of ESD failures in the world to date is around 25 trillion dollars, it is inevitable to take ESD measures wherever it is used in manufacturing and using advanced technology. Aircraft maintenance and production facilities, intensive care units, radar control units, emar and x-ray rooms, printing houses, operating theaters, data processing centers, pharmaceutical industry, electrical electronics manufacturing assembly and testing units are examples.

ESD is basically; equipment and equipment that can be easily affected by the environment, or the voltage sensitivity of the components used at very high sensitivity. Static electricity has been known to have an overwhelming effect for a few thousand years. Recently, these effects have just begun to be understood and the advantages and disadvantages of these effects have been observed in many applications. Unfortunately, some undesirable situations of static electricity cause problems. Many circuit elements, components, circuits, high-tech products cause unwanted failures and poor product quality due to the sudden change of electrostatic charge. This means; This means that there is an energy charge in the environment ie electrostatic charge discharge or ESD for short. Equipment affected by ESD; transistors, diodes, laser diodes, electro-optical devices, precision film resistors, thin and thick film resistors, capacitors, different semiconductors, microcircuits, hybrid devices, piezoelectric crystals, and even more complex integrated circuit devices can be easily affected by the ESD environment. elements. Many electrostatic generators include a triboelectric charge; this can be explained as a contact contact that may occur between the two materials, followed by the separation of the contact points. In such an action, the movement of the electrons will be from one surface to the other, creating a charge imbalance between the materials. At this time, ESD can directly damage the charging sources or charging objects directly at the time of contact. These situations prove to us how effective and negative the power of ESD is in our working life.

Precautions against ESD:
All conductors and personnel in the work area are in direct contact with the ground. This contact creates an equal potential between all conductors and working personnel. The voltage potential (O) in the ground is greater than zero and has the same potential in all other elements. Continuous protection measures should be taken against this potential. The entire work area (EPA) is protected by sensitive and remarkable ESD symbols and signs and the work area must be protected from ESD by marking before personnel enter the area.

The isolation and isolation required in the processes are to prevent the electron flow of the conductors and thus provide an ionization system.
In an ESD protected outdoor area, the sensitive ESD bag forms a protection shield, such as a faraday cage, against triboelectric charge. These bags are protected against discharge from electrostatic fields (EPA) and from penetration into the ground. Staff and visitors entering the work area; grounding should be provided by wearing wristbands or heel straps, gloves or handrails. ESD aprons should be worn regularly, working points and documents should be kept in a protector.
Cleaners containing silicone should not be used. Because such materials prevent the conductivity of the insulated layer or the proper functioning of the dissipative material, to clean the ESD covers; ESD cleaners containing static dissaative and solution should be used.
In terms of personnel safety, old or perishable material must be replaced with a new one. Faulty earth breaker and other safety guards should be emphasized. However, employees are constantly in contact with electrical sources wherever they are.
A detailed study is required for ESD control environmental design (markings), product inspection, testing, storage, loading, use, maintenance, renovation and repair.