Patent ID: 7968959
Filing Date: 2011-06-28
Classification: H01L,Y02E,Y02P

Abstract:
1. A method of fabricating a thick semiconductor drift detector having a front side and a back side, including drift electrodes and a collecting electrode, using a gray tone lithography operation in combination with a plasma etching operation, and applying a plurality of voltages, the method comprising: forming the collecting electrode in a semiconducting substrate on the front side; forming, using gray-tone lithography by photo-sculpting resist films to create a plurality of 3D profiles in photo-resist; etching the semiconducting substrate conforming to a plurality of trenches having various depths created on the back side, wherein etching includes reactive ion etching operations; forming junctions inside the plurality of trenches in the form of a plurality of drifting electrodes on the back side; forming a plurality of junctions on the front side in the form of a plurality of drifting electrodes on the front side; forming electrical contacts on the plurality of drifting electrodes on the front and the plurality of drifting electrodes on the back side; forming an electrical contact on the collecting electrode; and applying a plurality of voltages at the plurality of drifting electrodes on the front side and at the plurality of drifting electrodes on the back side, causing the semiconducting substrate to be fully depleted between neighboring trenches of the plurality of trenches and causing generated charge carriers to drift towards the collecting electrode.