An experimental study of the reactive ion etching rie of. A plasma creates ions, and neutral species that are drawn to a biased electrode. Recent citations editorial for achieving atomistic control in plasma material interactions gottlieb s oehrlein et althis content was downloaded from ip address 128. These conditions result in plasma etching processes which can be grouped into four cate gories. Plasmatherm 790 rie reactive ion etcher basic operation guide description.
From neutral gases and glow discharge utilization, chemically reactive species are generated to react with materials being etched to form volatile byproducts. Such rapid progress is what has enabled the semiconductor industry. Etching deep reactive ion etcher drie the plasmatherm versaline drie system is an inductively coupled plasma icp etch system for deep silicon etching using the bosch process. Ee143 f2010 lecture 14 etching university of california. Reactive ion etching rie is a wellestablished technol ogy in the semiconductor industry for etching polymeric dielectrics. The surface of the component is etched with a reactive process gas. Technology development of 3d silicon plasma etching. Material from the surface is etched away, converted to the gas phase and removed by the vacuum system. Effect of potential field on ion deflection and shape. Plasma etching techniques are typically classed by the configuration of the electrodes.
A conformal polymer is deposited, and then the polymer read more etching. An experimental study of the reactive ion etching rie of gap using bcl 3 plasma processing s. It refers to a parallel plate hardware arrangement where the substrate is placed on a biased electrode the cathode facing a grounded electrode. A conformal polymer is deposited, and then the polymer. Macroloading is a function of total exposed area reacting with gas phase. Reactive ion etching process development and characterization.
As for the chemical plasma etching, the name for the synergetical plasma etching systems is not straightforward. Plasma assisted etching and deposition of thin films using reactive gas glow discharges is currently in wide spread use in the microelectronics industry 1. 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, temperature, and pressure. Keywords euv sn etching reactive ion etching collector cleaning insitu plasma hydrogen snh 4 decomposition introduction in just the past 30 years, the minimum feature size on an integrated circuit has shrunk from 1 lmto11nm1, 2. Deep reactive ion etching of pyrex glass using sf6 plasma. In a pure oxygen plasma, surface accumulation of antimony from the photoinitiator.
However, despite the importance of plasma processing, reactive gas glow discharges are not well understood. Subdamagethreshold plasma etching and profile tailoring of. Advanced plasma etch chambers are equipped with a lot of knobs for controlling. The plasma is generated under low pressure vacuum by an electromagnetic field. Reactive ion etching systems rie etch process plasma etch. The inductively coupled plasma etching of sio2 was carried out using sf6, cf4 and chf3.
Reactive ion etching of y2o3 films applying f, cl and clbr. In such plasma, decomposition of sf produces f radicals that etch silicon spontaneously isotropically by formation of volatile sif. Dry etching, also called plasma etching, sputters or dissolves the materials using reactive ions in a gas phase. Plasma etching, or reactive ion etching rie, is an important unit operation that is used to remove thin films. It is a highly controllable process that can process a wide variety of materials, including semiconductors, dielectrics and some metals. Plasma etching and reactive ion etching models the model we studied is based on the idea of. Chemical dry etching of silicon nitride and silicon. A series of etching experiments, conducted according to an l9 34 orthogonal array, was carried out on a plasmalab pc5100 reactive ion etcher plasma technologyuk ltd. Berkeley ee143 f2010 lecture 15 1 reactive ion etching r ie plasma wafers rf. 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.
Elevated electrode temperatures 150 c are commonly used to increase the volatility of the incl x byproducts and reduce micromasking. During rie etching processes, volatile compounds are formed in interaction of sample surfaces and highenergy ionsradicals generated by lowpressure plasma. The highest etch rate is obtained when a relatively low oxygen. Guidelines for etching silicon mems structures using fluorine. Reactive ion etching of y2o3 films applying f, cl and cl. Reactive ion etching rie is the simplest configuration of dry etching equipment. The plasma is generated under low pressure by an electromagnetic field. Substrates up to 8 inches in diameter are manually loaded into the process chamber. Oehrleinb department of physics, the university of albany, state university of new york, 1400 washington avenue. Reactive ion etching rie is an etching technology used in microfabrication. For all gas combinations, with the exception of cl2, the etch rate was found to be similar, indicating a primarily physical etch process, enhanced in cl2 by an additional chemical etching component.
The deep silicon etching dse process alternates between deposition and isotropic etching in a chamber with an icp configuration. The side effects of this operation are over etching and nonuniformity. Berkeley ee143 f2010 lecture 14 2 etch process figures of merit etch rate etch rate uniformity selectivity anisotropy. Deep reactive ion etching drie is a standard technique for silicon micro and.
High verticality inpingaasp etching in cl2h2ar inductively. Introduction to plasma etching willson research group. Reaction probability of radicals depends on substrate temperature. One of the processes that is most frequently used to remove material in an anisotropie manner was pioneered by hosokawa et al 5 in 1974 and is commonly referred to as reactive ion etching rie. We prefer reactively assisted ion beam etching raibe instead of reactive ion etching. Reactiveion etching rie is an etching technology used in microfabrication. The addition of a magnetic field parallel to the wafer holder reduces.
A plasma generates reactive species which are not available in a bottle and delivers them to the substrate typical species in the plasma electrons neutral reactive radicals. The mechanisms of reactive ion etching are discussed by flamm et al. Inductively coupled plasma icp reactive ion etching rie has become widespread for etching inp based structures. Here also, a discussion of nomenclature is in order. Since the pressure in a typical plasmaetching system is on the order of 100 mtorr, the knudsen number the ratio of the mean free path of any gas particles to the characteristic length of the surface.
Watson research center, yorktown heights, new york 10598 received 1 april 1991. Etching with only cl 2 gas has been shown to produce smooth sidewalls with selectivity of 20. The temperature of the plasma etching table was kept at 10c, and the forward and reflected powers were maintained at 200 w and zero respectively. Plasma etching techniques including rie, pe, icp, and drie. Plasmaassisted etching and deposition of thin films using reactive gas glow discharges is currently in wide spread use in the microelectronics industry 1. A plasma is created whenever gases are forced to conduct electric current plasmas generate electrons, reactive neutral species, and ions a plasma is a quasineutral gas of charged and neutral particles quasineutral means that overall the net charge of the plasma is.
It utilizes plasma instead of liquid etchants to remove the materials, which is more precise, controllable and repeatable compared to wet etching, but a more expensive vacuum system is required. Rie is a type of dry etching which has different characteristics than wet etching. Chemical dry etching of silicon nitride and silicon dioxide using cf4o2n2 gas mixtures b. 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. Removal of tin from extreme ultraviolet collector optics by. For all gas combinations, with the exception of cl2, the etch rate was found to be similar, indicating a primarily physical etch process, enhanced in cl2 by an additional chemicaletching component. Etching process development of sio2 etching using inductively. Controlled chemical plasma etching for advanced technology applications page 2 pressure usually in the 100 to 200 mtorr range provides the anisotropic nature of the plasma, and the increased power compensates for the lack of ions to increase the etch rate. Reactive ion etching systems rie etch process plasma. Removal of tin from extreme ultraviolet collector optics. Surfaces of sige alloy films after 5 min of reactive ion etching, i. Numerical simulation of a singlewafer isothermal plasma. Parametric reactive ion etching of inp using cl2 and ch4 gases jae su yu and yong tak lee.
Guidelines for etching silicon mems structures using. Plasmatherm 790 rie reactive ion etcher basic operation. Advanced dry etching studies for micro and nanosystems dtu. Knowledge of vacuum fundamentals, one was able to design and fabricate an rf reactor. Edc plasma plasma discharge zones paschenslaw erf plasma ehighdensity plasmas edrie microloading silicon grass 172005 eel6935 advanced mems spring 2005 instructor. The plasmatherm 790 is configured for rie reactive ion etching processing of silicon substrates.
Plasma surface etching plasma surface etching is a type of plasma treatment used to increase the surface area of a material on the microscopic scale. Plasma etching of materials can proceed via a combination of physical and chemical mechanisms. Ee143 f2010 lecture 14 1 etching etching terminology etching considerations for ics wet etching reactive ion etching plasma etching professor n cheung, u. Subdamagethreshold plasma etching and profile tailoring.
Mar 25, 2019 plasma processing done to fabricate integrated cells is known as plasma etching. Reactive ion etching of silicon using fbased chemistry. Deep reactive ion etching of microstructures in pyrex glass applying sf6 plasma was investigated in li et al. Reactive ion etching of sige alloys using hbr tim d. Ee143 f2010 lecture 14 6 3 etching selectivity s wet etching s is controlled by. Mechanisms for plasma and reactive ion etchfront roughening. Rie uses chemically reactive plasma to remove material deposited on wafers. The volatile compounds are removed from the sample surfaces, and isotropic or anisotropic. Reactive ion etching rie, also known as plasma etching or dry etching, and its extension deep reactive ion etching drie are processes that combine physical and chemicals effect to remove. Reactive ion etching rie is a high resolution mechanism for etching materials using reactive gas discharges.
Reactive ion etching of yttrium oxide thin films was investigated using cf4o2, bcl3, hbr and cl2 inductively coupled plasmas. Highenergy ions from the plasma attack the wafer surface and react with it. Process variables are saved in recipe files on the control computer hard drive. Plasma etching is extremely sensitive to many variables, making etch results inconsistent and irreproducible. Index termscryogenic etching, profile control, reactive ion.
Reactive ion etching systems rie plasma etching samco inc. Reactive ion etching rie is a major process in the fabrication of semiconductor devices for transferring patterns from masks to semiconductor substrates. Modeling and simulation of plasma etching reactors for. Plasma processing done to fabricate integrated cells is known as plasma etching. Deep reactive ion etching drie was critical with rie. Reactive ion etching rie is a plasma etching technology to fabricate micro and nanostructures. Plasmatherm 790 rie reactive ion etcher basic operation guide. Reactive ion etching is an anisotropic processreactive ion etching is an anisotropic process. Etching hydrocarbon polymers by rte is usu ally performed in an oxygen plasma, and forms volatile and thermodynamically stable products such as co, co and hgo.
It is also known as dry etching as the traditional etching is carried out by the involvement of various wet. Energy and vacuum is needed to maintain plasma gas discharge. One major advantage to rie over other forms of etching is that the process can be designed to be highly anisotropic, allowing for much finer. From neutral gases and glow discharge utilization, chemically reactive species are generated to react with materials being. Theoretical simulation of shape evolution of etching fea tures has been carried out for a number of processes in cluding reactive ion etching 15, ion milling, sputtering 16, and plasma etching 17. Studies of the reactive ion etching of silicongermanium. Pdf a survey on the reactive ion etching of silicon in.
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