Hi Yan Xin, normally I have not very good results using AZ5214 in HF etching processes due to adhesion problems. After some time (~1/2 min), HF tends to lift the resist (depending on your surface preparation). Furthermore, AZ5214 is not resistant against penetration of HF through the resist - you'll get partly exposed surfaces after a couple of minutes. We use ARP-3510, or even better, ARP-3100 (both from Allresist) for long HF etching processes. I think you burn your resist at 400°C and you might not be able to remove it afterwards. Best Daniel -----Original Message----- From: mems-talk-bounces+d.grimm=ifw-dresden.de@memsnet.org [mailto:mems-talk- bounces+d.grimm=ifw-dresden.de@memsnet.org] On Behalf Of Xin Yan Sent: Wednesday, November 17, 2010 4:44 AM To: General MEMS discussion Subject: [mems-talk] AZ5214E and anodic bonding Hi everyone, What's the effect of AZ5214E to the 400degreeC anodic bonding process? Here is the process flow: 1 DRIE Si with a ...(...2um gap-2um line-2um gap-2um line...) ...structure, this area is about 200um long*30um width*50um depth. 2 Thermal oxidation for 2um oxide layer (wet oxidation for about 10 hours) 3 spin the photoresist AZ5214E as positive tone for thickness of 1.5um, then Photolith. the 2um gap-2um line area is protected by the photoresis. note: in this step, AZ5214E will leak in to the trench in the 2um gap-2um line area. the resist could stay in the trench til the next step. and the top edge of trench could exposure to the BOE solution, *Question 1: how badly the BOE will attack the lateral oxide layer side of the trenches of in the 2um gap-2um line area ?* 4 BOE etch oxide layer away of the other area except the 2um gap-2um line area 5 etch 7740 for a cavity. 6 allign the cavity to the 2um gap-2um line area and perform the anodic bonding process under the temperature about 400 degreeC. *Question2: What's the effect of residual AZ5214E in the trench to the 400degreeC anodic bonding process? * any suggestions will be appreciated. Best Regards, Yan Xin -Pen-Tung Sah MEMS Research Center, -Xiamen University, CHINA XMU HOME: http://memsc.xmu.edu.cn/mems_renchaiduiwu/XuYuan_Chen-Group/index_1.html