摘要:

Therma‐Probe tool has long been established to monitor the implant dose. In this work, we demonstrate that the unmodified tool is also capable of meeting the stringent demands of junction depth monitoring for the current and future technology nodes. The ultra‐shallow junction (USJ) application development was carried out on the Therma‐Probe tool using the wafers provided by the International SEMATECH. The measured Therma‐Wave signal varies as a sinusoidal function of the SIMS‐based junction depth (at 1E18 ions/cm3) for wafers with various dose and energy conditions annealed around 1000°C. A theoretical model has been proposed to explain the source of the experimental signal response to the junction depth. A correlation table may be set up using the junction depth values provided by a reference method such as SIMS (Secondary Ion Mass Spectrometry) or SRP (Spreading Resistance Profiling); or the sheet resistance obtained using a 4‐point probe system. The existing user interface software has been modified to allow reporting the results directly terms of the correlated junction depth. For production‐worthy throughput conditions, the short‐term precision is found to be <0.5Å, while the long‐term stability is shown to be <2 Å for a variety of wafers tested. The USJ application package for the Therma‐Probe tool offers a method to monitor wafers using an in‐line, fast, and non‐destructive metrology in production. © 2003 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1622541

出版商:AIP    

年代:1903

数据来源: AIP

摘要:

X‐ray metrology techniques have emerged from the laboratory to meet the challenges of the production fab. X‐ray Reflectometry (XRR) and X‐ray Fluorescence (XRF) are non‐destructive methods to probe film thickness, density, roughness, and composition. What has kept x‐ray metrology out of the fab for so long is large spot size, low throughput, and difficult analysis. Combining small‐spot XRR and XRF techniques, today’s x‐ray metrology covers a wide range of applications from front‐end to back‐end, transparent to metal, ultrathin to micron‐thick, on blanket and patterned wafers with speed and with automated data analysis. This work focuses on copper barrier applications. © 2003 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1622542

出版商:AIP    

年代:1903

数据来源: AIP

摘要:

Although the capability of scanning capacitance microscopy (SCM) for pn junction imaging has been qualitatively demonstrated, quantification of dopant profiles in two‐dimensions for pn junctions has proven to be a challenging problem. One reason is that the SCM result is seldom reproducible and this is generally believed to be due to sample preparation technique. In the first part of this work, we made a detailed study of sample preparation methods for SCM measurements. The purpose of the study was to establish an optimum sample preparation technique. Experiments were performed on two known dopant profiles: n type and p type staircase structures with concentration ranging from 1014to 1019cm−3. These two samples were cross‐sectioned and prepared using different oxidation techniques, which caused variations of interface states and oxide quality. We studied the effect of wet oxidation, thermal oxidation, as well as combined wet and thermal oxidation. Experimental parameters : temperature, baking duration and oxidation methods were studied in detail. To evaluate the oxide quality, we measured the flat band voltage change &Dgr;VFBby sweeping dC/dV vs. voltage in forward and reverse direction (from accumulation to depletion & vice versa). &Dgr;VFBrepresents the amount of the oxide trap charge. Since the staircase structure sample has a large doping range, the contrast reversal effect was obvious. We could minimize this effect by using the optimum experimental condition. In the second part, we investigated samples prepared under this optimum experimental condition. © 2003 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1622543

出版商:AIP    

年代:1903

数据来源: AIP

摘要:

Due to the continuous shrinkage of semiconductor devices, the use of a good 2D‐profiling technique is essential as these structures are entirely two‐dimensional and dopant nor carrier profiles are accessible with the standard 1D profiling techniques such as SRP and SIMS. In this work we present the application of SCM in support of the process development for a wide range of novel devices, such as trenchMOSFET, vertical RESURF diode, bipolar transistor. In all these applications, one of the most important issues to get good qualitative results is the sample preparation of the device. Therefore the sample preparation was optimized to get the best contrast in doping concentration at the same time avoiding the effects of contrast reversal. Also SCM at different dc‐bias in amplitude and phase mode is investigated in more detail. We systematically observe for both p‐ and n‐type a phase shift for high voltages as well as a large shift of the flatband voltage. With this knowledge reliable results are achieved for the different devices and especially measuring in phase mode offers more advantages in delineating p‐ and n‐type regions in comparison to SCM in amplitude mode. © 2003 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1622544

出版商:AIP    

年代:1903

数据来源: AIP

摘要:

Within this paper we present a general study on the resolution limits of scanning spreading resistance microscopy (SSRM) and scanning capacitance microscopy (SCM). The definition of the resolution concept is not straightforward for carrier profiling techniques and has to be divided into three main parameters: the spatial resolution, the dopant gradient resolution and the concentration sensitivity. Dedicated structures were conceived and processed for this analysis. The present study shows that the SSRM technique has a good spatial resolution (better than 3 nm), dopant gradient resolution (a few nm/dec) and concentration sensitivity. This excellent performance of the SSRM technique can probably be explained by the intimate contact between the probe and the sample and by the absence of stray effects. The SCM technique also offers a reasonable spatial resolution but suffers from a lower signal to noise ratio that may affect its practical use. © 2003 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1622545

出版商:AIP    

年代:1903

数据来源: AIP

摘要:

In this paper, we present the overall progress in scanning spreading resistance microscopy (SSRM) capabilities, achieved over the last year, with respect to all aspects of the technique. Progress in spatial resolution (less than 3 nm) has been achieved by optimized sample preparation and the development of better hard conductive diamond tips. Limitations in tip (and sample) lifetime have been reduced by the introduction of a more sophisticated, damage reducing tip movement and pressure control procedures. Data interpretation has been improved by the introduction of automated quantification software and the development of a more advanced model for the diamond tip‐semiconductor contact, including the impact of the surface states at the polished sample surface. © 2003 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1622546

出版商:AIP    

年代:1903

数据来源: AIP

摘要:

Ultra shallow dopant profiles are one of the major challenges for ULSI silicon metrology. Following the ITRS 2002, the 90nm technology node will appear in 2004 along with the maximum drain extension in the range of 15–25 nm for both P‐MOS and N‐MOS devices. In this frame, a very abrupt junction with a decay length of 4 nm/decade is mandatory. A depth resolution better than 0.7 nm in profiling shallow implanted dopants is consequently required. In this review, after a brief summary on necessities and difficulties of (N‐MOS) ultra shallow profiling for the 90 nm technology node, we present a comparison between two Secondary Ions Mass Spectrometry (SIMS) approaches using different instruments (Magnetic Sector and Time of Flight Spectrometers) for the characterization of arsenic ultra shallow profiles. A particular relevance is dedicated to the methodological optimization and data processing, mainly in quantification and depth scale determination. Quantitative SIMS results have been compared with complementary techniques like LEXES, MEIS and RBS. © 2003 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1622547

出版商:AIP    

年代:1903

数据来源: AIP

摘要:

The heterodyne laser interferometer installed on the new Cameca SC‐Ultra SIMS apparatus permits an in situ depth evaluation during depth profiling. The aim of this work is an investigation of the laser interferometer advantages and limitations for profiling of dopants in silicon. The laser depth calibration has been compared with the one determined by measuring the crater final depth with a stylus mechanical profilometer. Some experimental conditions where this approach can provide accurate results have been identified and confirm the usefulness of this device. © 2003 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1622548

出版商:AIP    

年代:1903

数据来源: AIP

摘要:

We are evaluating the use of bevel depth profiling Secondary Ion Mass Spectrometry (SIMS) for the characterization of layered semiconductor materials. In this procedure, a sub‐degree angle bevel is cut into the analytical sample with an oxygen or cesium primary ion beam in a commercial SIMS instrument. The elemental distribution of the resulting bevel surface is then imaged with a focused ion beam in the same instrument. This approach offers maximum flexibility for depth profiling analysis. The primary beam energy, incident angle and species used to cut the bevel can be optimized to minimize ion beam mixing and surface topography independent of the conditions used for secondary ion analysis. In some cases, depth resolution can be greater than available from conventional depth profiling. Removal of residual surface damage/topography created during beveling has also been investigated by the cleaning of the bevel surfaces using gas‐cluster ion beam sputtering before imaging analysis. © 2003 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1622549

出版商:AIP    

年代:1903

数据来源: AIP

摘要:

The coupling of laser ablation systems with inductively coupled plasma (ICP) mass spectrometry has been done for many years, however the quantitative aspects as well as the applications have often been limited. Recently, LA ICP‐MS has been developed into a valuable analytical tool in our laboratory to address new applications, and some experimental difficulties encountered by SEM‐EDX and SIMS in characterizing solid semiconductor, electronic, and optical communication materials. In this paper we will discuss many of the applications as well as the pros, cons, and complementary features of the laser ablation technique as it relates to electronics industry issues. © 2003 American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.1622550

出版商:AIP    

年代:1903

数据来源: AIP