Schematic band diagrams at metalsemiconductor contacts without interface states. Gold contacts are often formed by electroless deposition however this forms a complex interface. Use features like bookmarks, note taking and highlighting while reading metal semiconductor contacts and devices issn. Pdf metalsemiconductor contact in organic thin film.
Metalsemiconductor contacts monographs in electrical and electronic engineering rhoderick, e. Metal oxide semiconductor gas sensors in environmental. Among semiconductor nanomaterials, zno is one of most promising. They can behave either as a schottky barrier or as an ohmic contact dependent on the characteristics of the interface. Metal to semiconductor ms junctions are of great importance since they are present in every semiconductor device. Nov 02, 2015 metalsemiconductor contacts kasif nabi imi2015007 department of microelectronics indian institute of information technology allahabad 2nd november 2 november 2015 1 2.
B is significantly higher than the thermal energy kt, the semiconductor is depleted near the metal and behaves as a schottky barrier. Metalsemiconductor interfaces rectifying schottky junction nonrectifying ohmic contacts 4. A detailed analysis of the metalsemiconductor contact. The general structure is a lightly doped ptype substrate, into which two regions, the source and the drain, both of heavily doped ntype semiconductor have been embedded. An ohmic contact is a nonrectifying electrical junction. Work purpose the determination of the potential difference that appears at the contact surface between a metal and a semiconductor, potential difference that is known under the name of contact, or diffusion, bias. In this study, we have chosen the most commonly used contact test structures to measure contact resistance rc and extract. Our knowledge of metal semiconductor diodes is more than a century old. Metalsemiconductor contact in organic thin film transistors article pdf available in journal of materials chemistry 1845. Ultraviolet photoresponse characteristics of diamond diodes.
Often the metal is there just to serve as a contact to pn junctions in the semiconductor. Schottky, who first proposed a model for barrier formation. Department of electronics engineering, national chiao tung university, hsinchu, taiwan. Metalsemiconductor contacts 1988 edition open library. Whether a given metalsemiconductor junction is an ohmic contact or a schottky barrier depends on the schottky barrier height. The effect of interface states on the barrier heights of metal semiconductor contacts was first analyzed by cowley and sze 33. Importance of metal semiconductor contacts is due to l ohmic metal semiconductor junctions e. Pellegrini centro di studio per i metodi e i dispositivi di radiotrasmissione, consiglio nazionale delle ricerche, universitdi pisa, via diotisalvi n.
Metal semiconductor interfaces rectifying schottky junction nonrectifying ohmic contacts 3. Rhoderick, 9780198593362, available at book depository with free delivery worldwide. Topics covered include the currentvoltage relationship, the capacitance of rectifying contacts, and practical methods of fabricating contacts. Metalsemiconductor contacts kasif nabi imi2015007 department of microelectronics indian institute of information technology allahabad 2nd november 2 november 2015 1 2. Metalsemiconductor ohmic contacts stanford university. It is highly desirable that metal oxide semiconductor sensors have a. The small barrier that exists for electron flow from metal to the semiconductor, but vanishes when. Before discussing the behaviour of a metal semiconductor boundary, it is first necessary to introduce the concept of the work function. The term metal silicon contact includes silicidesi contacts.
It is well known that the quality of metalsemiconductor contacts plays an. Metalsemiconductor ohmic contacts rcsd r dp rext rov x y 0 sidewall gate silicide nextx novy year 1997 1999 2003 2006 2009 2012 min feature size 0. Description and verification of the fundamental current. For example, good ohmic contacts are essential for achieving excellent performance of a semiconductor device, while schottky i. Everyday low prices and free delivery on eligible orders. Electrical properties of metal semiconductor contacts digital.
Gold has a work function closely matching that of high resistivity cdznte and is a popular choice of contact metal. The presentday semiconductor technology would be inconceivable without extensive use of schottky barrier junctions. Written for semiconductor technologists and physicists engaged in research on semiconductor interfaces, this text emphasizes practical implications wherever they are relevant to device technology. Metal semiconductor contacts and devices, volume 1st edition.
Download for offline reading, highlight, bookmark or take notes while you read metalsemiconductor schottky barrier junctions and their applications. Low resistance ohmic contacts are used to allow charge to flow easily in both directions between the two conductors, without blocking due to rectification or excess power dissipation due to voltage thresholds. Overview of electronic properties of semiconductor. Properties that are significant to device operation for integrated circuits. Lecture 17 metalsemiconductor junction march 14, 2007 contents.
Rhoderick, metalsemiconductor contacts, clarendon press, oxford 1978. Written for semiconductor technologists and physicists engaged in research on. Differences of electron work function between metal and semiconductor lead to the rectification behavior named schottky effect 2. Rhoderick, metal semiconductor contacts, clarendon press, oxford 1978. Metal semiconductor contacts, pn junctions, bipolar transistors, and mos fieldeffect transistors. Metal semiconductor contacts and devices issn kindle edition by cohen, simon s. The work function of a material is the energy required to remove an electron from the level of the chemical potential and give it enough energy to escape to infinity and arrive there with zero energy. Metalsemiconductor contacts fermi level pinning is the lack of barrier height modulation with metal work function due to either large density of intrinsic states. Doitpoms tlp library introduction to semiconductors metal. To improve the contacts, the interface formed between metal and semiconductor during contact deposition must be better understood.
Metal semiconductor contact anchit biswas techno india,saltlake 2. For a sufficiently large schottky barrier height, where. Apr 20, 1978 topics covered include the currentvoltage relationship, the capacitance of rectifying contacts, and practical methods of fabricating contacts. Metalsemiconductor contacts monographs in electrical and. Metal semiconductor contacts and devices issn, cohen. This option allows users to search by publication, volume and page selecting this option will search the current publication in context. Metalsemiconductor contacts schottky contacts metal on lightly doped silicon rectifying ohmic contacts metal on heavily doped silicon low resistance 2 november. The metal oxide semiconductor field effect transistor mosfet is one of the cornerstones of modern semiconductor technology. Metalsemiconductor interfaces metalsemiconductor contact schottky barrierdiode ohmic contacts mesfet ece 663 ece 663 device building blocks schottky ms pn junction hbt mos ece 663 energy band diagram of an isolated metal adjacent to an isolated ntype semiconductor qfsc ec ef ktlnncnd for ntype eg ktlnnvna for ptype ece 663 energy band. Metalsemiconductor contacts are an obvious component of any semiconductor device. Ideal metalsemiconductor junction outside equilib rium reading assignment. Metalsemiconductor contacts, pn junctions, bipolar transistors, and mos fieldeffect transistors. Written for semiconductor technologists and physicists engaged this second edition brings a greatly expanded treatment of the physics of schottkybarrier formation to its comprehensive discussion of. Metalsemiconductor contacts monographs in electrical and electronic engineering.
The presentday semiconductor technology would be inconceivable without extensive use of. Rhoderick, 1988, clarendon press, oxford university press edition, in english 2nd ed. Interfaces between metal and semiconductor may be found almost everywhere in contemporary electronics. I have two of the same contacts on each sample so imagine the iv of two head to toe diodes. Rhoderick 1978 dealing with the basic principles of metal semiconductor contacts and a few. Metalsemiconductor schottky barrier junctions and their. Characterization of the metalsemiconductor interface of. At other times, the metalsemiconductor interface itself performs essential electronic functions. Selecting this option will search all publications across the scitation platform selecting this option will search all publications for the publishersociety in context. A fundamental difference between a metal and a semiconductor is that the former is unipolar, whereas a semiconductor is bipolar. Braun, 1 in 1874, reported the rectifying nature of metallic contacts on copper, iron, and lead sulfide crystals. Metalsemiconductor interfaces rectifying schottky junction nonrectifying ohmic contacts 3.
A short discussion is also given of practical contacts and their application in semiconductor technology, and a comparison. Metal semiconductor interfaces rectifying schottky junction nonrectifying ohmic contacts 4. At the same time, such contacts cannot be assumed to have a resistance as low as that of two connected metals. A rhoderick is the author of metal semiconductor contacts 4. Theory when two substances are in contact, between them there is a charge. In particular, a large mismatch between the fermi energy of the metal and semiconductor can result is a highresistance rectifying contact.
Quantifying the barrier lowering of zno schottky nanodevices under. Since 1962 it has been known that absorption or desorption of a gas on the surface of a metal oxide changes the conductivity of the material, this phenomenon being first demonstrated using zinc oxide thin film layers. Printed in great britain a detailed analysis of the metal semiconductor contact b. Physics of schottky barrier junctions springer for research. It is well known that the quality of metalsemiconductor contacts plays an important role in the performance of various semiconductor devices and integrated circuits. Metalsemiconductor schottky barrier junctions and their applications ebook written by b. High contact resistances can be due to a schottky barrier height.
This second edition brings a greatly expanded treatment of the physics of schottkybarrier formation to its comprehensive discussion of modern semiconductor technology. This test pattern will be inserted in a test vehicle dedicated to monitor this process. A rectifying metal semiconductor contact is known as a schottky barrier after w. Schematic band diagrams at metal semiconductor contacts without interface states. Metallic contact between mos2 and ni via au nanoglue cover page pdf available in small 1422 may 2018 with 152 reads how we measure reads. The sensitivity of a surface to a gas can be as low as parts per billion ppb 25. This second edition brings a greatly expanded treatment of the physics of schottkybarrier formation to its comprehensive discussion of modern. Metal semiconductor contacts are an obvious component of any semiconductor device.
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