RAPID ISOTHERMAL ANNEALING OF ION IMPLANTED SILICON DEVICES BY UNIFORM LARGE AREA IRRADIATION WITH A NEW ELECTRON BEAM SYSTEM

On a préparé des diodes ayant de bonnes caractéristiques électriques par recuit isothermique rapide de silicium 100 lourdement dopé par implantation de P+ et As+. Les traitements thermiques ont été effectués en irradiant d'une manière uniforme la surface postérieure des échantillons avec un canon électronique de nouvelle conception. La redistribution des impuretés est grandement réduite, en comparaison avec un traitement thermique traditionnel à 1000°C pour 30 min. Enfin, les mesures de capacité-tension effectuées sur des structures MOS ont montré que ce traitement ne provoque pas de défauts dans l'oxyde quand on irradie la surface postérieure.Rapid isothermal annealing of P or As layers heavily implanted in Si wafers has been carried out by using a new electron beam system. Diodes with good electrical characteristics have been fabricated by irradiating the wafers on the back-side to a suitable thermal cycle. The impurity redistribution is greatly reduced as compared to conventional furnace annealing (1000°C, 30 min). Finally C-V measurements on MOS structures show that this technique does not cause significant oxide damage when the irradiation is performed on the back-side of the wafer

Tumor burden at diagnosis is the main clinical predictor of cell resistance in patients with early-stage, favorable Hodgkin lymphoma treated with VBM chemotherapy plus radiotherapy.

Abstract We verified whether early resistance to treatment can be predicted in a subset of patients with very favourable, early stage Hodgkin lymphoma, treated with VBM (vinblastine, bleomycin and methotrexate) chemotherapy and involved-field radiotherapy, an effective combination with very low early and late toxicity. The relative tumour burden (rTB) was volumetrically measured from the staging computed tomography and analysed together with the parameters of pre-therapy evaluation in 61 patients enrolled into the protocol MH-1b of the Gruppo Italiano Studio Linfomi between 1996 and 2003. Early failure, codified by either less than complete remission (i.e. partial/null response or progression) or early relapse (within 12 months from the end of therapy), was considered as clinical expression of resistance to treatment. Logistic regression and failure-free survival were the statistical tools for the analysis. The rTB demonstrated to be the best predictor of early failure, outperforming every other pre-treatment parameter, International Prognostic Score included. With a mean rTB value of 44.964 ± 34.788 cm(3)/m(2) in the 53 patients successfully treated and of 130.185 ± 63.993 cm(3)/m(2) in the eight with early treatment failure, the risk of resistance showed fivefold and 10-fold increases at rTB of 52.002 and 74.497 cm(3)/m(2), respectively. Only two patients relapsed more than 12 months after the end of therapy; both had a high initial rTB. The rTB is the best predictor of resistance also in the subset of patients with very favourable, early stage disease. Safe rTB limits are proposed for successful administration of VBM chemotherapy plus involved-field radiotherap

Tumor burden in Hodgkin's lymphoma can be reliably estimated from a few staging parameters

Abstract The relative tumor burden (rTB), the tumor burden normalized to body surface area, is of prime clinical and prognostic value in Hodgkin's lymphoma. However, its measurement is rather complicated and a bedside computation cannot be proposed. We investigated the possibility of estimating, instead of measuring, rTB from elementary parameters of the initial staging. The rTB of 507 patients, treated with therapeutic protocols of the Gruppo Italiano Studio Linfomi according to their staging characteristics, was measured through their pre-therapy computed tomographies. The relationships between rTB and staging characteristics were analyzed with simple and multiple regressions both in a training sample (254 patients) for a selection of predictive parameters, and in a test sample (253 patients) for validation of the results. The number of involved sites, bulky mass and the IPI score were the variables best related to rTB. The resulting final equation {estimated rTB=-4.3+8.3xIPI2+22.7x[no. of involved sites (+3 if a bulky mass is present)]} provided the maximal approximation to the measured rTB (R2=0.671). The validity of the equation was confirmed on the test sample and the predictive superiority of the estimated rTB over IPI was still evident in terms of failure-free survival in both groups of patients. The estimated rTB is accurate enough to retain most of the prognostic advantage of the measured rTB over the IPI score. It can be easily calculated, allows a valid approximation of the measured rTB, and can be proposed as a useful tool for clinical research and practice