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The discovery of enhanced piezoelectricity in solid solutions of AlN and ScN is certainly one of the most important events in piezoelectric MEMS. As compared to pure AlN, it brought a crucial factor 2 to 3 improvement in a number of figures of merit governing the performance of MEMS devices. The aim of this contribution is to give a short overview on actual topics in processing, properties, and applications in RF filters and sensors.

Scandium doped aluminium nitride (ScAlN) gained much attention during last years, since its piezoelectric response is much enlarged as compared to pure AlN films. Above 30% Sc the films are of high interest for piezoMEMS sensing and actuation, ultrasound generation, as well as energy harvesting applications. In this work, piezo-performance uniformity maps are presented for 20% and 33% Sc containing films, sputter deposited on 200-mm wafers. Furthermore, we employ a new method to determine the electro-mechanical coupling k(t)(2). Coupling results for various Sc/(Sc+Al) concentration (0, 6, 20, 26, 33%) are shown. In addition, the dielectric constant epsilon(r) and dielectric loss tan delta, and the transversal and the longitudinal piezoelectric coefficients, e(31,f) and d(33,f,) were measured. The wafers show a high with-in-wafer uniformity (1 sigma uniformity < 2% for Sc20Al80N and < 1% for Sc33Al67N). The highest coupling k(t)(2) = 21.2% was achieved for a 33% Sc film. The presented Al-Sc property-uniformity maps provide a good foundation for ScAlN based MEMS device design and manufacturing.

Aim To assess patient-reported outcome measures (PROMs), aesthetics and stability of root coverage procedures from a previous 6-month RCT after 1 year. Material & Methods 45 patients (90 recessions) had received a coronally advanced flap (CAF = control) only or a xenogeneic collagen matrix in addition (CAF + CMX = test). Visual analogue scales (VAS) and questionnaires were used for PROMs and the root coverage aesthetic score (RES) for professional aesthetic evaluations. Results VAS scores (patient satisfaction) amounted to 8.58 ± 1.86 (test) versus 8.38 ± 2.46 (control). 6 patients preferred CAF+CMX concerning surgical procedure and aesthetics, 6 preferred CAF and 29 were equally satisfied. RES was 7.85 ± 2.42 for the test group versus 7.34 ± 2.90 for the controls. Root coverage (RC) was 76.28% for test and 75.05% for control defects. The mean increase in keratinized tissue width was higher in test (from 1.97 to 3.02 mm) than in controls (2.00 to 2.64 mm) (p = 0.0413). Likewise, test sites showed more gain in gingival thickness (0.52 mm) than control sites (0.27 mm) (p = 0.0023). Compared to 6 months, clinical outcomes were stable Conclusions Results for PROMs, RES and RC did not significantly differ between treatment groups. Thickness and width of keratinized tissue were enhanced following CAF + CMX compared to CAF alone. This article is protected by copyright. All rights reserved.

The enhancement of the electromechanical coupling coefficient caused by Sc substitution in AlN-based piezoelectric MEMS devices can be exploited successfully only if the dielectric losses remain confined to low values. While the magnitude of the piezoelectric activity in Al 1-x Sc x N thin films has been described widely in the literature, the impact of the Sc content on the loss tangent has not been studied extensively. In this work we discuss the dissipation factor obtained for x=0.095 and x=0.3 on Mo and Pt bottom electrodes, for full capacitor stacks deposited with an EVATEC Clusterline®200–II PVD tool equipped with single alloy targets 304mm in diameter.

Recent literature has focused on improving piezoelectric coupling coefficients by alloying aluminum nitride (AlN) with scandium (Sc). Akiyama et al. showed the highest d_33 piezoelectric coefficient increase of >4x at a 41% Sc substitution for Al. Thus far, studies mainly focus on material measurements such as x-ray diffraction or piezoelectric constants to assess the material quality. Although these measurements are useful to assess the improvement in the piezoelectric performance of the material, they do not address improvements in the figure-of-merit (FOM) of resonators (i.e., coupling coefficient times quality factor). Resonator structures are needed to directly extract these key performance parameters for film assessment. Fabrication integration, however, must be minimized to avoid obscuring film performance by extrinsic device effects.

Recent literature has focused on improving piezoelectric coupling coefficients by alloying aluminum nitride (AlN) with scandium (Sc). Akiyama et al. showed the highest piezoelectric coefficient increase of nearly four times for a 41% Sc substitution for Al. Thus far, studies mainly focus on material measurements such as x-ray diffraction or piezoelectric constants to assess the material quality. Although these measurements are useful to assess the improvement in the piezoelectric performance of the material, they do not address changes in the coupling coefficient and quality factor. Resonator structures are needed to directly extract these key performance parameters for film assessment. Fabrication integration, however, must be minimized to avoid obscuring film performance by extrinsic device effects. In this work, we assess a film evaluation tool using contour mode resonators (CMRs) to directly extract resonator performance for film comparison. Resonators formed from AlN, Sc 0.06 Al 0.94 N, and Sc 0.125 Al 0.875 N films are compared to demonstrate the method.

Organic passivated silicon wafers, composite substrates such as silicon on glass or Fan-out Wafer-Level Package (FOWLP) technology all pose new challenges for UBM and RDL processes [1]-[5]. Materials used in these substrates must be adequately degassed for subsequent plasma processing under vacuum but their heat-sensitive nature necessitates careful thermal management. Selecting the proper technology for each individual step enables the definition of a high yield process, minimizing contamination from the organic materials. This paper discusses the preferred degas principles for different substrates and applications. Temperature simulation data and experimental results are presented for various heating methods including single wafer and batch processes. It illustrates the effectiveness of an atmospheric batch degasser for removal of volatile water and organic compounds (VC) at moderate temperatures below 150°C. The results will be compared with standard vacuum degas technologies and the resulting contact resistance (Rc) values after subsequent low temperature ICP etch will be reported. The paper also addresses the etch process requirements to ensure efficient pumping of remaining volatile contaminants, the required temperature management of the substrates and the particle containment and cleanliness of the process environment.

Meyle J, Hoffmann T, Topoll H, Heinz B, Al-Machot E, Jervoe-Storm P-M, Meis C, Eickholz P, Jepsen S: A multi-centre randomized controlled clinical trial on the treatment of intra-bony defects with enamel matrix derivatives/synthetic bone graft or enamel matrix derivatives alone: results after 12 months. J Clin Periodontol 2011; doi: 10.1111/j.1600-051X.2011.01726.x. Abstract Objectives: Comparison of the clinical and radiographic outcomes of a combination of enamel matrix derivatives (EMD) and a synthetic bone graft (EMD/SBG) with EMD alone in wide (2 mm) and deep (4 mm) one- and two- wall intra-bony defects 12 months after treatment. Materials and Methods: Seventy-three patients with chronic periodontitis and one wide (2 mm) and deep (4 mm) intra-bony defect were recruited in five centres in Germany. During surgery, defects were randomly assigned to EMD/SBG (test) or EMD (control). Assessments at baseline, after 6 and 12 months included bone sounding, attachment levels, probing pocket depths, bleeding on probing, and recessions. Changes in defect fill were recorded radiographically. Results: Both treatment modalities led to significant clinical improvements. In the EMD/SBG group a mean defect fill of 2.7 ± 1.9 mm was calculated, in the EMD group the defect fill was 2.8 ± 1.6 mm. A mean gain in clinical attachment of 1.7 ± 2.1 mm in the test group and 1.9 ± 1.7 mm in the control group after 1 year was observed. Radiographic analysis confirmed for both groups that deeper defects were associated with greater defect fill. Conclusion: The results show comparable clinical and radiographic outcomes following both treatment modalities 12 months after treatment.

Item does not contain fulltext OBJECTIVE: Evaluation of effects of patient factors on the outcome of regenerative treatment of buccal mandibular class II furcation defects. MATERIAL AND METHODS: Fifty-one patients were recruited. In the intention-to-treat population 21 patients were allocated into the sequence left treatment with enamel matrix protein derivative (EMD) and right guided tissue regeneration (GTR) and 27 in the sequence left GTR and right EMD. Evaluated patient factors were: smoking, age, gender, hypertension and oral hygiene status. Outcome parameters included change of: (a) horizontal depth of the defect at the deepest point (b) distance from the fornix of the furcation to bone crest of the defect, (c) distance from stent to the bottom of the defect, (d) pocket depth and (e) attachment level at the middle of the furcation. RESULTS: In patients 54 years of age and older, in males, in non-smokers and in patients with "poor" hygiene EMD-treated sites showed a significant higher mean reduction of the parameters d (age), b (gender, hygiene) a (smoking, hygiene) when compared with sites treated with GTR. CONCLUSIONS: These data provided an indication of a possible effect of patient factors on the outcome of regenerative treatment of buccal mandibular class II furcation defects.

The objective of this study was to evaluate the feasibility of a new polylactic acid bioabsorbable barrier in the treatment of gingival recession.Twenty patients with buccal recession defects (Miller class I, II, and III; mean recession: 4.0 +/- 1.2 mm; range: 2.0 to 6.8 mm) participated. After thorough scaling and root surface conditioning with 10% tetracycline-HCl, a trapezoidal mucoperiosteal flap was prepared. A customized barrier was applied to cover the defect. Barriers adhered directly to tooth and bone and no sutures were used. The barrier was subsequently covered by a coronally positioned flap. Assessments of probing depths were performed by means of a controlled-force electronic probe, and recession was determined on stone models with a digital caliper at baseline and 12 months following therapy.Eight barriers showed limited exposure (1 to 2 mm) with minimal signs of gingival inflammation between 2 and 6 weeks following surgery. Comparing baseline measurements with outcomes at 12 months, significant root coverage and probing attachment gain were observed (P0.0001, paired t test). Mean gingival recession was reduced to 0.4 +/- 0.5 mm, corresponding to a mean root coverage of 91.9%, and overall attachment gains amounted to 4.2 mm. A significant gain of keratinized tissue was found (2.9 +/- 0.7 mm), and mean probing depths were slightly reduced from 2.2 to 1.7 mm.The results of this study indicate favorable outcomes after using a new bioabsorbable barrier material for root coverage in recession-type defects.

It was the aim of this study to compare barrier membrane therapy with connective tissue grafts in the treatment of recession defects. Fifteen patients with 2 paired vestibular recession defects participated in the study. After thorough scaling and root surface conditioning with tetracycline-HCl, defects were randomly assigned to 1 of 2 treatment modalities. In one of the defects, a trapezoidal mucoperiosteal flap was prepared, and a titanium reinforced expanded polytetrafluoroethylene membrane was adapted to the defect and secured by a sling suture. The membrane was subsequently covered by a coronally positioned flap secured with crown attached sutures. The other defect was treated with a connective tissue graft employing the "envelope technique." Twelve months after therapy, both treatment modalities showed significant root coverage and probing attachment gain. Gingival recession decreased from 3.6+/-0.7 mm to 0.5+/-0.5 mm for membrane treated defects and from 3.6+/-1.0 mm to 0.5+/-0.5 mm following use of grafts, corresponding to mean root coverages of 87.1% and 86.9%, respectively. Mean gains of keratinized tissue of 1.5 mm (membrane) and 2.5 mm (graft) could be observed. Thus, the results of this study demonstrate that both titanium reinforced barrier membranes and connective tissue grafts can be successfully used to treat periodontal recession defects.

Aim To evaluate the clinical outcomes of the use of a xenogeneic collagen matrix (CM) in combination with the coronally advanced flap (CAF) in the treatment of localized recession defects. Material & Methods In a multicentre single-blinded, randomized, controlled, split-mouth trial, 90 recessions (Miller I, II) in 45 patients received either CAF + CM or CAF alone. Results At 6 months, root coverage (primary outcome) was 75.29% for test and 72.66% for control defects (p = 0.169), with 36% of test and 31% of control defects exhibiting complete coverage. The increase in mean width of keratinized tissue (KT) was higher in test (from 1.97 to 2.90 mm) than in control defects (from 2.00 to 2.57 mm) (p = 0.036). Likewise, test sites had more gain in gingival thickness (GT) (0.59 mm) than control sites (0.34 mm) (p = 0.003). Larger (≥3 mm) recessions (n = 35 patients) treated with CM showed higher root coverage (72.03% versus 66.16%, p = 0.043), as well as more gain in KT and GT. Conclusions CAF + CM was not superior with regard to root coverage, but enhanced gingival thickness and width of keratinized tissue when compared with CAF alone. For the coverage of larger defects, CAF + CM was more effective.

Objectives: Comparison of the outcomes of a combination of an enamel matrix derivative and a synthetic bone graft (EMD/SBC) with EMD alone in wide intra-bony defects. Material and Methods: Seventy-three patients with chronic periodontitis were recruited in five centres in Germany. All patients had one wide intra-bony defect of 4 mm. Surgical procedures involved microsurgical technique and the modified papilla preservation flap. After debridement, defects were randomly assigned to EMD/SBC (test) or EMD (control). Assessments at baseline and after 6 months included bone sounding, attachment levels, probing pocket depths, bleeding on probing and recessions. Early wound-healing, adverse effects and patients' perceptions were also recorded. Results: Both treatment modalities led to significant clinical improvements. Change in bone fill 6 months after surgery was 2.0 mm (± 2.1) in the test group and 2.1 mm (± 1.2) in the control group. A gain in clinical attachment of 1.3 mm (± 1.8) in the test group and 1.8 mm (± 1.6) in the control group was observed. One week after surgery, primary closure was maintained in 95% of the test sites and 100% of the control sites. No differences in patients' perceptions were found. Conclusion: The results of the present study showed similar clinical outcomes following both treatment modalities.

A spin coating technique for the 100 micron cover layer for Blu-Ray Disc production has been developed. The process includes a controlled manipulation of the viscosity of the lacquer with heat and UV light during spin coating. Stability and cost efficiency, two vital criteria for mass production, have been considered. Keywords: Optical Storage, Spin Coating, Blu-Ray Disc 1. INTRODUCTION With the Blu-Ray Disc, the 3rd generation of optical storage media is today appearing on the consumer market. While moulding and sputtering processes for substrate preparation and functional layer application are very similar to the currently used processes for CD and DVD production, the reliable and cost efficient application of a highly precise, 100 P m thick optical layer on top of the information layer is the challenging production step for this format. Since the very beginning of the Blu-Ray Disc, there have been two techniques discussed between media developers, equipment manufacturers, consumables suppliers and media producers for the 100 P m cover layer production: Spin coating of a UV curable resin is seen as one candidate, bonding a cover layer sheet stands as the alternative. Looking at the foil bonding technology one has to distinguish between PSA-sheet bonding and UV-resin bonding of a thin polycarbonate sheet. The PSA sheet bonding is a proven method which gives excellent cover layer thickness homogeneity. The PSA adhesive is supplied together with the foil and the manufacturing process of the disc is relatively simple. But due to the high cost per sheet it can only be seen as a start-up technology for the Blu-Ray Disc media family. It is not seen as an attractive solution for economic mass production because the cost per sheet cannot be reduced significantly. The foil bonding technology using UV-resin combines a spinning process and a bonding process similar to standard DVD bonding technology. A UV-curable resin is applied onto the BD substrate, spread over the disc in a spin coating process and combined with the foil, preferably in a vacuum bonding process, and finally the system is cured under UV irradiation. Like PSA-sheet bonding, foil bonding technology us ing UV-resin is a practical way to go. In both cases it is the quality of the foil which significantly de termines the quality of the cover layer. Using a spin coating process

This multicenter, randomized trial compared enamel matrix derivative (EMD) with barrier membranes for the treatment of Class II mandibular furcations with regard to secondary outcomes. The influence of furcation morphology on the effectiveness of either treatment was also evaluated.Forty-eight patients (age range 28 to 73 years; 22 females, 26 males) with buccal Class II furcation involvements in both contralateral lower first or second molars were included. After initial periodontal treatment, defects were randomized to either EMD or bioabsorbable guided tissue regeneration (GTR) barrier. Study design and the results for the primary parameter were previously described. Results of the following secondary outcome variables are reported here: changes of the hard tissue boundaries describing the anatomical situation of the furcation defect and changes in the following clinical parameters between baseline and 14 months: plaque, level of gingival margin, probing depth, bleeding on probing, attachment level, and bone sounding at five sites/tooth at the buccal side. Descriptive statistics were applied for changes in clinical parameters and measurements of hard tissue boundaries. The differences observed under treatment with EMD or membrane were analyzed by means of the Wilcoxon two-sample test. The difference between the effect of the EMD and membrane treatment was estimated by means of the Hodges-Lehmann estimator.Overall, similar healing results were observed for both treatments. However, there was slightly more recession in the mid-furcation site following membrane treatment (P = 0.04). Additionally, different treatment effects could be detected for the distances from the stent or cemento-enamel junction (CEJ) to the buccal bone crest, mid-distal root (Pstent = 0.01; PCEJ = 0.07) and for the distance from the stent or CEJ to the buccal bone crest, mid-mesial root (Pstent = 0.01; PCEJ = 0.01). There was no measurable bone resorption in EMD sites, whereas a slight resorption occurred with membrane treatment. Furcation morphology at the time of surgery was not associated with clinical outcome, irrespective of the treatment.With regard to secondary outcome parameters, enamel matrix derivative treatment led to a similar regenerative result as the membrane procedure.