Role of the dense amorphous carbon layer in photoresist etching. Oxygen and tetrafluoromethane cf 4, when mixed together for use in plasma etching, create the oxyfluoride ion of. Comparison of argon and oxygen plasma treatments on led. In a reactive ion etch rie, a chemical reaction is used to weaken the bonding of the surface of the material and assist the sputtering process.
Used for any materials insulating and conductiveused for any materials insulating and conductive. Argon plasma etching has reported to enhance contact angle from 52 deg to 68 deg, and, oxygen plasma etching to reduce contact angle from 52 deg to 19 deg for cfrp composites for bone plate applications. Mechanisms of silicon etching in fluorine and chlorine. Role of the dense amorphous carbon layer in photoresist. Analysis of the etching of silicon in an inductively coupled chlorine plasma using laser thermal desorption jae y. At very low pressure, the ion energy is high, reactant. Ion milling is a physical etching technique whereby the ions of an inert gas typically ar are accelerated from a wide beam ion source into the surface of a substrate or coated substrate in vacuum in order to remove material to some desired depth or underlayer. Argon and reactive ion beam etching for saw devices. Dry etching overview the college of engineering at the. The argon ion and chlorine atom molecular fluxes were controlled independently over more than an order of magnitude and at flux levels within an order of magnitude of that typically used in high density plasma processes.
Ion beam etching ibe is a very promising technique in microelectronics because of its capability to etch small patterns with a high resolution and inert materials. Argon plasma inductively coupled plasma reactive ion. Pdf dry etching technology for semiconductors brookly namacejkovic reactiveion etching rie is an etching technology used in microfabrication. Plasma developable resists of good reactive ion beam etching resistance are shown to have a sub micron line resolution capability.
Kinetic study of low energy argon ionenhanced plasma. Radical a neutral gas particle atom or molecule that exists in a state of incomplete chemical bonding and is therefore chemically reactive. Analysis of the etching of silicon in an inductively. Physics of highpressure helium and argon radiofrequency plasmas. This anisotropic feature can be further enhanced by allowing the deposition of certain passivating films to occur along vertical sidewalls during the plasma reaction. Argon plasma cleaning of fluorine, organic and oxide. Please refer to the table below for information and the link to access safety data sheets on argon available from central welding supply website. Plasma etching plasma etching involves physical bombardment of the substrate by an ion which is nominally inert. Characterization of argon plasma by use of optical emission.
Related content hydrofluorocarbon ion density of argon or kryptondiluted ch2f2 plasmas. The most common plasma etch configurations are reactive ion etch rie, planar etch pe, inductively coupled plasma etch icp etch, or deep reactive ion etch drie etch. Etching steps are done either with assistance of a plasma source sputter cathode, arc cathode, or gas ion source, giving a lineofsight effect for the argon ions respectively for the metal ions in case of arc etching, or by a glow discharge generated on the substrate holder by pulsed power, dcpower, or rfpower supplies connected to the. Noble gases like argon and helium are often used to dilute a gas mixture.
Reactive ion etching of gaas and algaas has been performed by using ccl2f202ar 2 and cc12f2he mixtures 3, while plasma etching at higher pressures than are typically associated with rie has been reported for using ccl4, bcc12, and cl 2 0 2 46. Ion bombardment at ion energies of the order 100s of ev is typical of plasma based patterntransfer processes and results in the formation of a dense amorphous carbon dac layer on the surface of a. Ion and electronassisted gassurface chemistryan important. Argon plasma can be used for surface modifications in thierrys plasma technology systems. Similar to the situation with argon, nitrogen ions.
Single and multilayered materials processing by argon ion. Reactive ion etching rie is the simplest configuration of dry etching equipment. Silicon nitride etching performance of ch2f2 plasma diluted with argon or krypton yusuke kondo, kenji ishikawa, toshio hayashi, yudai miyawaki, keigo takeda, hiroki kondo, makoto sekine, and masaru hori. Like other dry plasma etch techniques, the typical. The sputtering yields are plotted against the poisoning ratio the poisoning ratio is defined as the ratio of the rate of arrival of oxygen molecules at the target surface to that of the. Reactive ion etching is an anisotropic processreactive ion etching is an anisotropic process. Plasma etching page 14 the plasma state ion, positive a positively charged particle a gas molecule or atom with and electron removed. Weve developed a wide range of solutions for plasma cleaning, plasma etching, reactive ion etching rie, plasma treatment, surface modification, and other facets of plasma processing. Rie uses chemically reactive plasma to remove material deposited on wafers. Effect of oxygen addition to an argon plasma on etching. Dry etching technologies plasma etching is dominated by chemical erosion. Im using argon plasma etching to increase layer to layer adhesion during ni electroplating with photoresist as the mask.
Thus, a lot of dry etching techniques were developed involving different types of plasma 3. Silicon etching in fluorine and chlorinecontaining plasmas 1711 as pressure is decreased below about loomtorr, the potential across the discharge characteristically increases, and with this there is a corresponding rise in sheath potentials. It involves a highspeed stream of glow discharge plasma of an appropriate gas mixture being shot in pulses at a sample. Because plasma strength at the ground electrode is lower than that at the powered electrode, the sse by oxygen plasma. The plasma is generated under low pressure by an electromagnetic field. Argon plasma inductively coupled plasma reactive ion etching. Here the plasma is in contact with the wafer and ion bombardment is used to increase the etch rate and to achieve ani sotropy. One commercial process for cutting inkjet printer nozzles uses sandblasting. The process is used to remove oxide contamination from the. Plasma based dry etching rf power is used to drive chemical reactions plasma takes place of elevated temperatures or very reactive chemicals types. Since the sheath potential depends on the electrode surface area ratio, a large potential up to 2 kv may be present in front of the smallest electrode, leading to reactive ion etching. The argon plasma is also capacitive with the current leading the voltage by 79.
Aug 05, 20 this is a view of a silicon wafer o100mm being argon ion sputter etched at 10 mtorr in one of our reactors. Physical constants and conversion factors quantity symbol value boltzmannconstant k 1. A plasma creates ions, and neutral species that are drawn to a biased electrode. Model etch profiles for ion energy distribution functions. Although many tools have been created to do this, the most finely honed tool is the inductively couple plasma reactive ion etcher. Ion enhanced etching or reactive ion etching rie it has been observed that chemical and physical components of plasma etching do not always act independently both in terms of net etch rate and in resulting etch profile. The key applications and benefits of using ion beam technology for etching processes in comparison to technology such as plasma etching will be presented. The process is used to remove oxide contamination from the silicon prior to metal or. Rie processes can also be used for surface preparation prior to deposition or other process steps. Plasma etching typically high pressure, no ion bombardment. The pattern transfer step is for trilayer lithography where the photoresist etches down to a silicon dioxide mask and the trench is etched in the substrate. Then, the ibe technique applied to multilayered stacks tiniau, tinicuau, bst and pzt of a few hundred nanometers is studied. The etch rates of 620 combinations of these were measured.
Plasma etching involves physical bombardment of the substrate by an ion which is nominally inert. The plasma is generated under low pressure vacuum by an electromagnetic field. Argon is also used as a carrier gas in chromatography, icp plasma, sputtering, plasma etching and ion implantations. Argon plasma etching, selectivity and effect of other. Argon plasma etching, selectivity and effect of other metal presence. This model is perfect for manufacturers, medical facilities, universities, research facilities, or any other company in need of a costeffective, productiongrade plasma processing solution. Silicon nitride etching performance of ch2f2 plasma. Plasma etching is a form of plasma processing used to fabricate integrated circuits. It is shown that the sputtering yield of various materials submitted to argon ion 1 ke v bombardment decreases strongly with increase of oxygen pressure in the atmosphere of the sputtering chamber.
Reactive ion etching inductively coupled plasma for low damage etching. Comparison of argon and oxygen plasma treatments on led chip bond pad for wire bond application. Structuring or removal of the epoxy based, photo sensitive polymer su8 by inductively coupled plasma reactive ion etching icprie was investigated as a function of plasma chemistry, bias power. With sputter etching ion milling, the material is eroded physically by inert gas ions accelerated on the substrate. Lower ion energies, however, result in the lower etch rates and reduced g. Wintucky and mark christopher lewis research center cleveland, ohio and eugene bahnuik and simon wang case western reserve university cleveland, ohio prepared for the fifteenth international electric propulsion conference. The layer to be etched is removed by chemical reactions andor physical means ion bombardment. Rie ecrslr 740 plasma therm plasma therm has been building rie systems since the early 1970s with applications in al metal etching on inline systems. On the use of h2 plasma for the cleaning and passivation of inp substrates.
The etch rates of thermal oxide in different dilutions of hf and bhf are also reported. Rie is a type of dry etching which has different characteristics than wet etching. This tool has the ability to finesse structures from silicon unachievable on other machines. On the use of h2 plasma for the cleaning and passivation. The pe100 is a complete plasma treatment solution capable of reactive ion etching, plasma functionalization, and more. Publishers pdf, also known as version of record includes final page, issue and volume numbers. Not surprisingly, the surface finish is rather poor and there are issues with particles contaminating the devices. The reaction products must be volatile and are carried away in the gas stream. Plasma etching is a synergistic process of both chemical and physical etching, which makes it distinctive from conventional wet etching.
Plasma etching is widely used for etching nanoscale features because it can produce vertical sidewall profiles with little or no undercut. Highenergy ions from the plasma attack the wafer surface and react with it. Plasma etching techniques including rie, pe, icp, and drie. Singular sheet etching of graphene with oxygen plasma. A summary of these xps results is shown in the table below. Dry etching substrates are immersed in a reactive gas plasma. These results contribute to a better understanding of mechanisms occurring in the argon discharge and provide efficient control on the electron plasma parameters. Nov 08, 20 time dependence of etching depth in argon plasma shows that etching rate decreases by more than half after etching to a depth of around 15 nm.
The plasma source, known as etch species, can be either charged ions or neutral atoms and radicals. This paper models the etch profiles for a long trench for ion energy distribution functions in an inductively coupled plasma icp reactor. Pdf reactive ion etching of diamond in cf4, o2, o2 and arbased. Silicon nitride etching performance of ch 2 f 2 plasma diluted with argon or krypton to cite this article. The phase angle is shifted further for ar than for he, indicating that the ar plasma exhibits a higher resistance. Ion beam sputter etching of orthopedic implant alloy mp35sfa nkesulting effects on fatigue properties edwin g. Stripping of photoresist using a remote thermal aro2 and arn2o2. For example, etching silicon dioxide uses fluorocarbon species, which are known to also passivate the surface with teflon.
Technics ion mill etch rates university of minnesota. In this study, the angular incidence of an argon ion beam on the etch rate and uniformity is discussed in the case of several materials often used in microelectronics. An overview of ion beam generation is described, which will be followed by a discussion and presentation of some beneficial applications of ion beam technology. Plasma etching is one of the main applications of plasma treatment and the plasma system known as a plasma etcher is commonly used in production of semiconductor devices. Silicon nitride etching performance of ch2f2 plasma diluted. Plasma etching can change the surface contact angles, such as hydrophilic to hydrophobic, or vice versa. Argon is a chemically inert noble gas, meaning it will form very few or no chemical compounds. The technique for etching polymers is the use of a mixture of process gases. However, it is a physical process very like this that we need if we are to achieve a vertical etch profile. Summary of xray photoelectron spectroscopy xps results, before and after argon.
As a difference with ln etching using fluridebased gases the chemical reaction between li ion and the f does not take place and, as a consequence, the production of lif is completely eliminated. Etching different etching processes are selected depending upon the particular material to be removed. On the use of h2 plasma for the cleaning and passivation of inp substrates g. Plasma etching techniques are typically classed by the configuration of the electrodes. Comparison of argon and oxygen plasma treatments on led chip. Argon plasma can be generated in one of our lowpressure vacuum chambers and is used for plasma cleaning, surface activation and reactive ion etching. Introduction to plasma etching willson research group. Pdf the reactive ion etching of diamond in o2, cf4o2, chf3o2, o2ar discharges has been examined as a function of bias voltage, flow. Here, chemically reactive radial is formed in plasma and accelerated towards the substrate. Ion bombardment at ion energies of the order 100s of ev is typical of plasmabased patterntransfer processes and results in the formation of a dense amorphous carbon dac layer on the surface of a. Carbon levels were greatly reduced after argon plasma treatment.
Reactive ion etching rie is an etching technology used in microfabrication. The results of xps analysis of the pmma surface revealed that the reduction in etching rate is caused by a depletion of oxygen concentration by argon ion bombardment. Single and multilayered materials processing by argon ion beam. Kinetic study of low energy argon ionenhanced plasma etching. Pdf su8 etching in inductively coupled oxygen plasma.
Physical etching chemical etching reactive ion etching rie deep reactive ion etching drie plasma plasma partially ionized gas consisting of equal. Selective processes using highly polymerizing gases polymers condensate only on the wafer which is the coldest. Ion beam etching or milling is a dry plasma etch method which utilizes a remote broad beam ion plasma source to remove substrate material by physical inert gas andor chemical reactive gas means. Argon plasma etching with electroncyclotron resonance reactive ion etching has been proposed in 20. Since the 1980s, dry plasma etching is being applied for the removal of. Argon and oxygen ion chemistry effects in photoresist etching. Rie reactive ion etching represents a combination of physical and chemical erosion. The oxyfluoride ion is a powerful etching agent for polymeric. Argon ar and sulphur hexafluoride sf 6 gases were used as etching gases to investigate the influence of ion energy on the rie induced optical damage of gallium nitride gan. This can be done to control etch rate or to improve other aspects of the etch. Another difference between the helium and argon plasmas is that in the latter case the current wave form is not smooth but has a kink in it. Hui yuen peng, mutharasu devarajanteik toon lee, abstract the efficiencies of argon and oxygen microwave plasma treatments were compared in terms of contaminant removal and wire bond interfacial adhesionin this paper.
1146 181 1295 1437 100 1571 773 499 66 1294 668 1242 1006 356 607 1493 934 56 1470 823 170 382 1178 38 225 1476 24 1342 1416 1428 455 413 215