RF characteristics of 150‐nm AlGaN/GaN high electron mobility transistors fabricated using i‐line stepper lithography

Abstract This article reports radio frequency characteristics of 150‐nm gate aluminum gallium nitride (AlGaN)/gallium nitride (GaN) high electron mobility transistors (HEMTs) fabricated using i‐line stepper lithography and a thermal reflow technique. The authors have developed two different gate structures that were a field‐plated gate using the lift‐off process and a Y‐shaped gate using the ion‐milling process. Fabricated HEMTs using these different gate structures exhibited nearly equivalent DC characteristics. The field‐plated gate device showed a unity current gain cutoff frequency (fT) of 35 GHz and a maximum oscillation frequency (fmax) of 106 GHz, while the Y‐shaped gate device showed fT of 36 GHz and fmax of 115 GHz. The equivalent circuit analysis indicated a decrease in the gate‐drain capacitance and the drain conductance is responsible for the improved fmax in the Y‐shaped gate device

Extended pleurectomy/decortication and hyperthermic intraoperative intrapleural cisplatin perfusion for malignant pleural mesotheliomaCentral MessagePerspective

Objective: To evaluate the efficacy of multimodality treatment including extended pleurectomy/decortication (P/D) and hyperthermic intraoperative chemotherapy (HIOC) with cisplatin for malignant pleural mesothelioma (MPM), we investigated the pharmacokinetics of platinum, adverse events after HIOC, and survival outcome. Methods: Fifty-three patients with pathologically diagnosed MPM (cT1-3N0-1M0, excluding sarcomatoid) underwent an extended P/D and HIOC (cisplatin 80 mg/m2 in saline 2 L, 42°C, 60 minutes) since 2011. The protocol includes postoperative 4 cycles of cisplatin and pemetrexed. Platinum concentrations in the perfusate (before and after) and the serum (1, 2, 4, 8, 24, 48, 72 hours after perfusion) were measured in 10 patients. Mortality and morbidity, especially adverse events of renal function, were investigated, and survival and affecting factors were examined. Results: All patients obtained macroscopic complete resection and pathologic staging revealed as follows: T1/2/3/4: 12/8/23/10, N0/1: 36/17, stage 1A/1B-3A/3B: 12/31/10, respectively. Platinum concentrations in the perfusate indicated that 28% of the dose remained in the pleural cavity, and the maximum concentration in the serum was 0.91 μg/mL. Six patients (11%) showed elevated max-creatinine (>2 mg/dL) postoperatively. Two patients (4%) received renal-replacement therapy, and one was weaned before discharge. There was no 30-day mortality and one in-hospital death (1.9%). Forty-six patients (87%) received multiple cycles of perioperative systemic chemotherapy. Median overall survival (OS) and disease-free survival (DFS) were 52.4 months and 18.7 months. Patents with stage 1A demonstrated a 5-year OS of 67.3% and a median DFS of 67.1 months, and patients with stage 1B-3A demonstrated a 5-year OS of 50.1% and a median DFS of 20.4 months. Univariate analysis showed histological subtype, p-T, p-stage, and multimodality treatment as significant factors affecting OS. Multivariate analysis revealed histology, p-stage, and multimodality as independent. Conclusions: Extended P/D and HIOC with cisplatin for MPM is acceptable with limited acute kidney injury. This multimodality protocol provides promising favorable survival for stage 1A-3A disease