Selective deposition with PH3 delta doping
Publication Date: 2013-Aug-19
The IP.com Prior Art Database
In conclusion, having a lower surface [P] by using delta-doping / vapor phase doping / atomic layer epitaxy techniques increases/enables ER selectivity of highly n-type doped layers during the n-type dopant concentration sensitive Cl2 based etch.
Summary of the technical contents of the invention
What problem does the invention solve?
Achieving/obtaining high levels of electrically active doping concentrations/levels (P,As,B, etc) and high levels of substitutional carbon concentration is desirable aiming for low resisitivity SiCP/SiP films.
Describe the existing solutions and their drawbacks.
When aiming for selective epitaxial growth (SEG) of very highly doped films using a Cl2 based cyclic deposition / etch (CDE) process the etch rate increases strongly with n-dopant level, diminishing etch rate selectivity. CDE processes offer substantial advantages over conventional SEG processes since deposition and etch can be independently optimized, allowing optimization of faceting and loading.
Describe the novelty features and the benefits of the proposed invention over the current solution.
The approach/technique of vapor phase doping (VPD), PH3 pre-deposition/PH3 delta doping, atomic layer doping/epitaxy (ALE) allows to enhance (P,C,..) dopant incorporation enabling/yielding very low resistivity SiCP/SiP films (e.g. 0.45mOhm-cm at 2.3% [C]sub). This approach utilizes vertical non-uniform dopant profiles burying the (P,C,..) dopants under a layer with different alloy composition effectively “shielding” all or some dopant form the surface exposed to the...