摘要:
Methods for fabricating a heterojunction bipolar transistor having a raised extrinsic base is provided in which the base resistance is reduced by forming a silicide atop the raised extrinsic base that extends to the emitter region in a self-aligned manner. The silicide formation is incorporated into a BiCMOS process flow after the raised extrinsic base has been formed. The present invention also provides a heterojunction bipolar transistor having a raised extrinsic base and a silicide located atop the raised extrinsic base. The silicide atop the raised extrinsic base extends to the emitter in a self-aligned manner. The emitter is separated from the silicide by a spacer.
摘要:
Methods for fabricating a heterojunction bipolar transistor having a raised extrinsic base is provided in which the base resistance is reduced by forming a silicide atop the raised extrinsic base that extends to the emitter region in a self-aligned manner. The silicide formation is incorporated into a BiCMOS process flow after the raised extrinsic base has been formed. The present invention also provides a heterojunction bipolar transistor having a raised extrinsic base and a silicide located atop the raised extrinsic base. The silicide atop the raised extrinsic base extends to the emitter in a self-aligned manner. The emitter is separated from the silicide by a spacer.
摘要:
The present invention provides a method for enhancing uni-directional diffusion of a metal during silicidation by using a metal-containing silicon alloy in conjunction with a first anneal in which two distinct thermal cycles are performed. The first thermal cycle of the first anneal is performed at a temperature that is capable of enhancing the uni-directional diffusion of metal, e.g., Co and/or Ni, into a Si-containing layer. The first thermal cycle causes an amorphous metal-containing silicide to form. The second thermal cycle is performed at a temperature that converts the amorphous metal-containing silicide into a crystallized metal rich silicide that is substantially non-etchable as compared to the metal-containing silicon alloy layer or a pure metal-containing layer. Following the first anneal, a selective etch is performed to remove any unreacted metal-containing alloy layer from the structure. A second anneal is performed to convert the metal rich silicide phase formed by the two thermal cycles of the first anneal into a metal silicide phase that is in its lowest resistance phase. A metal silicide is provided whose thickness is self-limiting.
摘要:
Methods of fabricating a semiconductor structure including heterogeneous suicides or germanides located in different regions of a semiconductor structure are provided. The heterogeneous suicides or germanides are formed onto a semiconductor layer, a conductive layer or both. In accordance with the present invention, the inventive methods utilize a combination of sequential deposition of different metals and patterning to form different suicides or germanides in different regions of a semiconductor chip. The method includes providing a Si-containing or Ge layer having at least a first region and a second region; forming a first silicide or germanide on one of the first or second regions; and forming a second silicide or germanide that is compositionally different from the first silicide or germanide on the other region not including the first silicide or germanide, wherein the steps of forming the first and second suicides or germanides are performed sequentially or in a single step.