Download or read book The Effects of Plasma Induced Damage on the Channel Layers of Ion Implanted GaAs MESFETs During Reactive Ion Etching RIE and Plasma Ashing Processes written by Hokyun Ahn and published by . This book was released on 2003 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: The gate length of GaAs MESFETs is required to be shorter for higher microwave frequency applications. The side-wall process using silicon nitride is one of the effective processes to fabricate short gate length GaAs MESFETs. The side-wall process consists of deposition and anisotropic etching of silicon nitride and delivers plasma induced damages on the channel layers of the devices. In this study, the effects of plasma induced damage on the channel layers of ion implanted GaAs MESFETs during reactive ion etching and plasma ashing processes have been investigated. The plasma induced damage was characterized by sheet resistance measurement, X- ray photoelectron spectroscopy(XPS) and auger electron spectroscopy(AES) of different etched surfaces, compared with a chemically wet-etched reference surface. Also the effect of the plasma induced damage on the device performance was investigated. As a result, plasma ashing can deteriorate the plasma-induced damage by RIE.
Download or read book Materials Issues for Tunable RF and Microwave Devices III Volume 720 written by Steven C. Tidrow and published by . This book was released on 2002-08-09 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt: Challenges facing the implementation of an affordable tunable RF and microwave device technology are discussed in these papers from an April 2002 meeting. Materials issues and devices are examined, with information on new tunable materials, issues of preparation and optimization of bulk and think film properties, material and surface characterization, evaluation of material loss and loss mechanisms, and effects of microstructure. At the device level, phase shifters are discussed and a new device concept for variable true time delay versus phase shift is introduced. At the system level, a paraelectric lens is used to demonstrate electronic beam steering of an antenna. Tidrow is affiliated with the US Army Research Laboratory. Annotation copyrighted by Book News, Inc., Portland, OR
Download or read book Plasma induced damage of GaAs During Etching of Refractory Metal Contacts written by and published by . This book was released on 1994 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effect of plasma-induced-damage on the majority carrier transport properties of GaAs has been studied by monitoring changes in sheet resistance (R{sub s}) of thin conducting layers under various plasma conditions including etch conditions for refractory metal contacts. R{sub s} determined from transmission line measurements are used to evaluate plasma-induced-damage for electron cyclotron resonance (ECR) and reactive ion etch (RIE) conditions by varying the thickness of doped epitaxial layers. The authors speculate that plasma-induced-damage in the near surface region plays a major role in explaining the damage mechanism observed in this study. Very consistent trends have been observed where R{sub s} increases with increasing ECR and RIE dc-bias, increasing microwave power, and decreasing pressure, thus showing R{sub s} increases as either the ion energy or ion flux increases. The authors have also observed that R{sub s} is lower for samples exposed to the RIE than the ECR, possibly due to higher ion and electron densities generated in the ECR and higher pressures in the RIE. It has also been observed R{sub s} dependence on ECR plasma chemistry where, R{sub s} is lower in SF6/Ar plasmas than Ar and N2 plasmas possibly related to interactions of F or S atoms with the GaAs surface. Moderate anneal temperatures (200 to 500°C) have shown significant R{sub s} recovery.
Download or read book Science Abstracts written by and published by . This book was released on 1995 with total page 1990 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Plasma Charging Damage written by Kin P. Cheung and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the 50 years since the invention of transistor, silicon integrated circuit (IC) technology has made astonishing advances. A key factor that makes these advances possible is the ability to have precise control on material properties and physical dimensions. The introduction of plasma processing in pattern transfer and in thin film deposition is a critical enabling advance among other things. In state of the art silicon Ie manufacturing process, plasma is used in more than 20 different critical steps. Plasma is sometimes called the fourth state of matter (other than gas, liquid and solid). It is a mixture of ions (positive and negative), electrons and neutrals in a quasi-neutral gaseous steady state very far from equilibrium, sustained by an energy source that balances the loss of charged particles. It is a very harsh environment for the delicate ICs. Highly energetic particles such as ions, electrons and photons bombard the surface of the wafer continuously. These bombardments can cause all kinds of damage to the silicon devices that make up the integrated circuits.
Download or read book Thin Oxide Damage by Plasma Processing written by Hyungcheol Shin and published by . This book was released on 1993 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Plasma Process induced Charging Damage on Thin Gate Oxides written by Donggun Park and published by . This book was released on 1998 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Plasma Reactive Ion Etching induced Damage in GaN written by Zoulikha Mouffak and published by . This book was released on 2003 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mechanistic Study of Plasma Damage to Porous Low k written by Hualiang Shi and published by . This book was released on 2010 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt: Low-k dielectrics with porosity are being introduced to reduce the RC delay of Cu/low-k interconnect. However, during the O2 plasma ashing process, the porous low-k dielectrics tend to degrade due to methyl depletion, moisture uptake, and densification, increasing the dielectric constant and leakage current. This dissertation presents a study of the mechanisms of plasma damage and dielectric recovery. The kinetics of plasma interaction with low-k dielectrics was investigated both experimentally and theoretically. By using a gap structure, the roles of ion, photon, and radical in producing damage on low-k dielectrics were differentiated. Oxidative plasma induced damage was proportional to the oxygen radical density, enhanced by VUV photon, and increased with substrate temperature. Ion bombardment induced surface densification, blocking radical diffusion. Two analytical models were derived to quantify the plasma damage. Based on the radical diffusion, reaction, and recombination inside porous low-k dielectrics, a plasma altered layer model was derived to interpret the chemical effect in the low ion energy region. It predicted that oxidative plasma induced damage can be reduced by decreasing pore radius, substrate temperature, and oxygen radical density and increasing carbon concentration and surface recombination rate inside low-k dielectrics. The model validity was verified by experiments and Monte-Carlo simulations. This model was also extended to the patterned low-k structure. Based on the ion collision cascade process, a sputtering yield model was introduced to interpret the physical effect in the high ion energy region. The model validity was verified by checking the ion angular and energy dependences of sputtering yield using O2/He/Ar plasma, low-k dielectrics with different k values, and a Faraday cage. Low-k dielectrics and plasma process were optimized to reduce plasma damage, including increasing carbon concentration in low-k dielectrics, switching plasma generator from ICP to RIE, increasing hard mask thickness, replacing O2 by CO2 plasma, increasing CO addition in CO/O2 plasma, and increasing N2 addition in CO2/N2 plasma. By combining analytical techniques with the Kramers-Kronig dispersion relation and quantum chemistry calculation, the origin of dielectric loss was ascribed to the physisorbed water molecules. Post-ash CH4 plasma treatment, vapor silylation process, and UV radiation were developed to repair plasma damage.
Download or read book Inductively coupled Plasma Reactive Ion Etching ICP RIE with HBR and Other Etch Chemistries of SI SIGE based Resonant Interband Tunnel Diodes Grown by Low Temperature Molecular Beam Epitaxy LT MBE written by Si-Young Park and published by . This book was released on 2006 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: The International Technology Roadmap for Semiconductors (ITRS) forecasts that current semiconductor technology based on the mainstream silicon CMOS platform is approaching its scaling of limit. One emerging technology which may augment CMOS and extend its operational lifetime is tunneling devices together with transistors. Tunnel diode based circuits have superior performance regarding high speed operation concurrently with low power consumption. Si-based resonant interband tunnel diodes (RITD) developed by this research group that are grown epitaxially using low temperature molecular beam epitaxy (LT-MBE), now enable monolithic integration with Si CMOS and SiGe technology. This thesis focuses on the study of the plasma damage from inductively- coupled plasma reactive ion etching (ICP-RIE) processes using several different process gases, various ICP powers and substrate bias powers compared to wet etching techniques on Si-based diodes grown using low temperature molecular beam epitaxial (LT-MBE). Of particular interest and promise is an HBr etch chemistry that provides hydrogen passivation while etching. The minimization from incident ion damage and residual surface contamination during dry plasma etching is one of the key issues in modern VLSI manufacturing, especially as transistors/devices are scaled to below 50 nm lengths. Many researchers, therefore, are still developing many advanced techniques to reduce and minimize plasma damage created by dry plasma etching process.
Download or read book Influence of SiCl4 Reactive Ion Etching on the Electrical Characteristics of GaAs written by D. Lootens and published by . This book was released on 1992 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: As the dimensions in optoelectronic components continue to shrink, more and more dry etching processes are used for patterning of the semiconductor material. Unfortunately the need for smaller dimensions requires anisotropic etching and so the use of energetic particles to stimulate the etching. Although RIE makes use of particles with relatively small energies (typically 2OOeV), the damage effects start playing a role, both in vertical direction and in lateral direction, as dimensions become smaller, like in quantum dots and wires. In literature, already a lot of work on REE-damage in GaAs has been reported, but only a few deal with the physical nature of the defects or with different doping types, although remarkable differences in the effect of particle bombardment on n-type and p-type have been reported and although the study of the different electrical behaviour of n- and p-type material, can reveal new information. The damage induced by the RIE-process can also be related to the chemistry of the reactive gases used. Our study covers electrical damage after SiCl4-RIE both in n- and p-type GaAs, involving capacitance-voltage (C-V) measurements on Schottky barriers and Deep Level Transient Spectroscopy (DLTS) measurements.
Download or read book Reactive Ion Etching of GaAs in a Magnetically Confined Plasma written by Joubran Jbara and published by . This book was released on 1987 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Inductively Coupled Plasma Induced Etch Damage of GaN P n Junctions written by and published by . This book was released on 1999 with total page 21 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plasma-induced etch damage can degrade the electrical and optical performance of III-V nitride electronic and photonic devices. We have investigated the etch-induced damage of an Inductively Coupled Plasma (ICP) etch system on the electrical performance of mesa-isolated GaN pn-junction diodes. GaN p-i-n mesa diodes were formed by Cl2/BCl3/Ar ICP etching under different plasma conditions. The reverse leakage current in the mesa diodes showed a strong relationship to chamber pressure, ion energy, and plasma flux. Plasma induced damage was minimized at moderate flux conditions (≤ 500 W), pressures ≥2 mTorr, and at ion energies below approximately -275 V.
Download or read book Reactive Ion Etching of Indium Phosphide based Heterostructures and Field effect Transistors Using Hydrogen Bromide Plasma written by Sambhulal Agarwala and published by . This book was released on 1994 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A new highly selective reactive ion etching process based on HBr plasma for the removal of InGaAs over InAlAs has been developed and the results are presented. The etch selectivity at a self-bias voltage of $-$100 V is over 160, which is the highest that has been reported for this material system so far. High etch selectivity is maintained over a wide range of chamber pressure and plasma self-bias voltages. The mechanism of this etch selectivity is determined to be due to the formation of involatile Al$sb2$O$sb3$. Selective HBr etching has been applied as the gate-recess process in the fabrication of InAlAs/InGaAs heterostructure FETs. Since less RIE-induced damage was observed in delta-doped structures, delta-doping was employed in all InP-based HFETs. The dc and rf device parameters of a typical 0.75-$mu$m gate-length transistor compare favorably with those of a corresponding device gate-recessed with a selective wet-etching technique. An extrinsic current-gain cutoff frequency of 150 GHz is obtained for a typical 0.2 $mu$m gate-length HFET device that was fabricated using selective HBr gate recess process. RIE-induced damage is characterized extensively using a variety of techniques such as AES, XPS, and SIMS analyses, Raman scattering, Hall measurements and Schottky characteristics. No significant degradation in surface properties is observed. The lattice damage in layer structures with 2DEG depth of greater than 20 nm was minimal. It is also observed that with increasing self-bias voltage the rate of removal of InGaAs increases faster than the rate of introduction of damage. An exponential distribution of damage with 1/e penetration depth of about 7.8 nm has been obtained. The exponential distribution of defects suggests that either ion channeling or diffusion is the possible mechanism of defect production in regions deeper than the projected range.
Download or read book Plasma Damaging Process of Porous Ultra low k Dielectrics and Dielectric Repair written by Huai Huang (Ph. D.) and published by . This book was released on 2012 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Ultra-low-k material is required to reduce the RC time delay in the integrated circuits. However, the integration of the porous low-k material into the on-chip interconnects was impeded by the plasma induced damage during etching and photoresist stripping processes. This dissertation aims to study the mechanism of plasma damage to porous ultra-low-k dielectrics with the objective to minimize the damage and to develop methods and processes to restore the low-k dielectric after the plasma damage. First, the plasma etching induced surface roughening was studied on blanket porous SiCOH films in the fluorocarbon based plasma. Substantial surface roughening was found in the low polymerization region, where the surface roughening process was initiated by the unevenly distribution of surface fluorocarbon polymers in the pore structure and enhanced by ion induced surface densification. With oxygen addition, the surface densification layer increased the radial diffusion rate difference between the top and the bottom of the pits, resulting in further increase of the surface roughness. The best process optimization was found at a "threshold point" where the surface polymerization level is just high enough to suppress the roughness initiation. The second part of this dissertation investigates the mechanism of the oxygen plasma damaging process. The roles of plasma constituents (i.e. ions, radicals and photons with different wavelengths) were differentiated by an on-wafer filter system. Oxygen radical was identified as the most critical and its damage effect was enhanced by photons with wavelength smaller than 185nm. The oxygen radical kinetics in the porous structure of low-k, including diffusion, reaction and recombination, was described analytically with a plasma altered layer model and then simulated with a Monte Carlo computational method, which give guidelines to minimize the damage. The analytical model of oxygen radical kinetic process is also used to investigate the oxygen plasma damage to patterned low-k structure, which is confirmed by experiments. Finally, the dielectric recovery was studied using silylation and UV broadband thermal treatment, both individually and in combination. After both vapor and supercritical CO2 silylation, surface carbon and hydrophobicity were partially recovered. However, the recovery effect was limited to the surface. In comparison, UV treatment can effectively remove water from the bulk of the damaged film and consolidate the silanol bonds with the help of thermal activation. The combination of UV and silylation treatments is more effectively for dielectric recovery than UV or silylation alone. The "UV first" treatment provided a better recovery in sequential processes. Under the same conditions, simultaneous treatments by silylation and UV irradiation achieved better bulk and surface recovery than the sequential process.
Download or read book Plasma parameter Dependence of Thin oxide Charging Damage to Microelectronic Test Structures in an Electron cyclotron resonance Plasma written by James Benedict Friedmann and published by . This book was released on 1995 with total page 692 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Investigation of Plasma Implantation and Gate Oxide Charging During Plasma Processing written by Barry Paul Linder and published by . This book was released on 1999 with total page 458 pages. Available in PDF, EPUB and Kindle. Book excerpt:
