Hi, 40-100 nm should do it, it depends upon your application. The thicker the Si3N4 the more voltage or higher temp etc, its a relationship between volts, current, density and temperature. you will need to experiment a bit, go for a thinner Nitride layer, but you will have to ask your coater what they can provide in terms of thickness. Best regards, Julian. ----- Original Message ----- From: "A.ALLOUCH"To: "General MEMS discussion" Sent: Wednesday, June 02, 2010 1:39 PM Subject: Re: [mems-talk] pyrex/pyrex anodic bonding Hi, Thank you for your answer. What about the thikness of SI3N4? best, Alaa Starlight a écrit : > Hi, > > Use an ion barrier such as Si3N4 to trap the Na+ ions, then a glass to > Si3N4 interface at 400 C should bond. > > Best regards, > > Julian.