Here is the abstract you requested from the IMAPS_2007 technical program page. This is the original abstract submitted by the author. Any changes to the technical content of the final manuscript published by IMAPS or the presentation that is given during the event is done by the author, not IMAPS.
|Direct Bonding of Langasite for High Temperature Applications|
|Keywords: High Temperature MEMS, Bonding, Langasite|
|We investigated direct bonding processes of langasite. Different kinds of activations were investigated and a new process was developed. The bonding process was successful, with bond forces close to silicon direct bonding. Thus, for example, sealed cavities could be fabricated monolithically. Monolithic structures are very important for systems working at high temperatures to avoid thermal stresses. The bonded interfaces were also investigated at elevated temperatures. Langasite is a new single crystal material with piezoelectric properties which shows piezoelectricaly induced bulk acoustic waves up to at least 1400 °C. In contrast the operating temperature of other piezoelectric materials like quartz or lithium niobate is limited to 520 °C and 400-500 °C, respectively. Additionally, langasite has a higher coupling factor than quartz and is not pyroelectrical. Hence it is a very interesting material for high temperature sensors and actuators in harsh environments in automotive, aircraft or industrial applications.Langasite is commercially available at wafer sizes of 4.|
|Erik Ansorge, Student
Magdeburg, Sachsen-Anhalt 39016,