MOCVD of Ni and Ni3C films from Ni(dmen)2(tfa)2

In this study results are reported on the transport and decomposition behavior of a trifluoroacetato complex of formula Ni(dmen)2(tfa)2, in view of its use as a precursor for the MOCVD of Ni. It is shown that Ni(dmen)2(tfa)2 can be sublimed up to 190 °C without decomposition with, however, a relatively low partial pressure. MOCVD of Ni films from this precursor on silicon and on silica are also reported, performed at temperatures varying between 275 °C and 350 °C. It was found that the process is kinetically controlled. Films are crystalline, present a granular morphology and, depending on operating conditions, are composed of Ni, of metastable nickel carbide Ni3C or of mixtures thereof. The carbon content decreases with decreasing deposition temperature and with increasing hydrogen flow rate. It is also higher in the first deposited layers, revealing a different decomposition mechanism of the precursor on an inert relatively to a metallic surface. Although processing conditions have not been optimized, MOCVD of Ni films from this family of complexes appears promising. However, modifications of the structure of Ni(dmen)2(tfa)2 are necessary to increase its volatility and consequently the growth rate of the films

Treatment of Primary Hypophysitis in Germany

Context: The best treatment of primary hypophysitis (PrHy) is a matter of debate. Objective: Our main objective was to analyze the treatment practice for PrHy in Germany and to compare the outcome of the main treatment options. Design: The Pituitary Working Group of the German Society of Endocrinology conducted a nationwide retrospective cross-sectional cohort study. Patients: Seventy-six patients with PrHy were eligible for the study. Main Outcome Measures: Clinical and endocrinological outcomes, side effects and complications of therapy, initial response, and recurrence rates were assessed. Outcome depending on the treatment modality was evaluated. Results: For mere observation, regression of space-occupying lesions was observed in 46%, unchanged size in 27%, and progression reported in 27%. Pituitary function improved in 27% of patients during observation. Deterioration of pituitary function was only found in patients with progressive lesions. The initial response to glucocorticoid pulse therapy was most favorable, with early failure in only 3%. However, the overall failure and recurrence rate was 41%. Recurrence rate was not related to duration of steroid administration. Side effects of steroids occurred in 63%. The surgical approach was transsphenoidal in 94%. The histological subtype was lymphocytic hypophysitis in 70% and granulomatous hypophysitis in 30%. Progression or recurrence was observed in 25% after surgical treatment. Conclusion: Glucocorticoid pulse therapy is associated with a high recurrence rate. Evidence suggests that surgery is not able to prevent recurrence. Considering the favorable results of observation, conservative management is recommended in PrHy unless symptoms are severe or progressive