We report on a Pt͑8 nm͒/Rh͑200 nm͒ metallization scheme for use in low resistance and high reflectance ohmic contacts to p-GaN for use in flip chip light-emitting diodes ͑FCLED͒ applications. The thermal annealing of a Pt/Rh contact at 500°C led to linear current-voltage characteristics with a specific contact resistance of 9.0 ϫ 10 Ϫ5 ⍀ cm 2 while the as-deposited Pt/Rh contact showed nonohmic characteristics. It was also shown that the 500°C annealed contact produces a high reflectance of 62% at a wavelength of 460 nm. Auger electron spectroscopy depth profiles and glancing-angle X-ray diffraction results indicated that the low contact resistance of the annealed sample can be attributed to the formation of Ga-Pt and Ga-Rh intermetallic phases. Furthermore, the electrical performance of an FCLED with the Pt/Rh reflector scheme was superior to that of a FCLED with a Ni/Au/Ag reflector scheme.

PurposeThe use of graft tissue fixation using bioabsorbable interference screws (BISs) in anterior cruciate ligament (ACL) reconstruction offers various advantages, but limited pullout strength. Therefore, additional tibial fixation is essential for aggressive rehabilitation. We hypothesized that additional graft tissue fixation using bioabsorbable suture anchors (BSA) would provide sufficient pull-out strength.Materials and MethodsTwenty four fresh frozen porcine distal femur and patellar tendon preparations were used. All specimens were divided into three groups based on additional fixation methods: A, isolated BIS; B, BIS and BSA; and C, BIS and post cortical screw. Tensile testing was carried out under an axial load. Ultimate failure load and ultimate failure load after cyclic loading were recorded.ResultsThe ultimate failure loads after load to failure testing were 166.8 N in group A, 536.4 N in group B, and 438 N in group C; meanwhile, the ultimate failure loads after load to failure testing with cyclic loading were 140 N in group A, 466.5 N in group B, and 400 N in group C. Stiffness after load to failure testing was 16.5 N/mm in group A, 33.5 N/mm in group B, and 40 N/mm in group C. An additional BSA fixation resulted in a significantly higher ultimate failure load and stiffness than isolated BIS fixation, similar to post screw fixation.ConclusionAdditional fixation using a BSA provided sufficient pullout strength for ACL reconstruction. The ultimate failure load of the BSA technique was similar to that of post cortical screws.

We introduce a new arthroscopic partial meniscectomy technique using a three portals and a small skin hook retractor to remove unstable inferior leaf in horizontal meniscal tear that involved the anterior portion of the lateral meniscus. The patient is positioned for a standard knee arthroscopy. After careful estimation of the depth and extent of the cleft and stability of the superior and inferior leaves is done through the standard anteromedial portal, a small skin hook retractor is inserted through the standard anterolateral portal to raise the dominant superior leaf of anterior horn, then the unstable inferior leaf is excised with a 90° rotary punch and a motorized shaver through the extreme far anteromedial portal. This technique is useful method to remove unstable inferior leaf of anterior horn of lateral meniscus which is difficult to remove with a standard technique.

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