A unique range of fully organic elastomers for semiconductor sealing applications which demand extreme plasma resistance. The Kimura® range of high performance elastomer materials utilize a controlled molecular architecture which provides a unique self-reinforcing polymer structure, elimiating the need for fillers of any kind. This high purity material breaks new ground in elastomer technology, developed specifically for aggressive semiconductor applications. Kimura® elastomers are NOT perfluoroelastomers or any other standard type of elastomer material. They are a new breed of elastomer, specifically developed by PPE, for the semiconductor industry, to offer a step-change in sealing performance, surpassing what has previously been achievable. The high purity of the polymer combined with the absence of any fillers makes Kimura® materials suitable for processes involving lower feature sizes. Kimura® materials also provide low coefficient of thermal expansion, low compression set and extremely low etch rates in aggressive plasma environments.