Aspects of the disclosure pertain to a system and method for providing an electron blocking layer with doping control. The electron blocking layer is included in a semiconductor assembly. The electron blocking layer includes a lithium aluminate layer. The lithium aluminate layer promotes reduced diffusion of magnesium into a layer stack of the semiconductor assembly.

Properties of a semiconductor device are improved. A semiconductor device having a superjunction structure, in which p-type column regions and n-type column regions are periodically arranged, is configured as follows. Each n-type column region has a vertical section including an n-type epitaxial layer located between trenches and a tapered embedded n-type epitaxial film disposed on a side face of the trench. Each p-type column region includes an embedded p-type epitaxial film disposed within the trench. The tapered embedded n-type epitaxial film is thus provided on the sidewall of the trench in which the p-type column region is to be disposed, thereby the p-type column region is allowed to have an inverted trapezoidal shape, leading to an increase in margin for a variation in concentration of a p-type impurity in the p-type column region. On resistance can be reduced by lateral diffusion of an n-type impurity (for example, As).

A semiconductor device is produced by providing a semiconductor substrate, forming an epitaxial layer on the semiconductor substrate, and introducing dopant atoms of a first doping type and dopant atoms of a second doping type into the epitaxial layer.

Substrate processing systems and methods include: (a) seating a substrate on a support; (b) optically measuring center substrate temperature using a first pyrometer; (c) optically measuring edge substrate temperature using a second pyrometer; and (d) determining an edge offset temperature between the edge substrate temperature and the center substrate temperature. Three temperature ramping steps are used to heat up the substrate for processing: two fast ramping steps and one slow ramping steps. After substrate processing, an initial, controlled cooling step is provided. During at least the second fast temperature ramping step, the slow temperature ramping step, the substrate processing step(s), and the initial controlled cooling step, heating of the substrate is controlled to place and/or hold the edge offset temperature within predetermined ranges in order to maintain uniform temperature and/or a desired temperature gradient across the substrate. Such systems and methods help avoid crystal defects (e.g., slip) and/or auto-doping.

What is proposed is a method of producing at least two differently heavily doped subzones (3, 5) predominantly doped with a first dopant type in a silicon substrate (1), in particular for a solar cell. The method comprises: covering at least a first subzone (3) of the silicon substrate (1) in which a heavier doping with the first dopant type is to be produced with a doping layer (7) of borosilicate glass, wherein at least a second subzone (5) of the silicon substrate (1) in which a lighter doping with the first dopant type is to be produced is not covered with the doping layer (7), and wherein boron as a dopant of a second dopant type differing from the first dopant type and oppositely polarized with respect to the same is included in the layer (7), and; heating the such prepared silicon substrate (1) to temperatures above 300 C., preferably above 900 C., in a furnace in an atmosphere containing significant quantities of the first dopant type. Additionally, at least a third doped subzone (15) doped with the second dopant type may be produced by the method additionally comprising, prior to the heating, a covering of the doping layer (7), above the third doped subzone (15) to be produced, with a further layer (17) acting as a diffusion barrier for the first dopant type.

The method uses the observation that a borosilicate glass layer seems to promote an in-diffusion of phosphorus from a gas atmosphere and may substantially facilitate a manufacturing for example of solar cells, in particular back contact solar cells.

Embodiments of the present disclosure relate to methods for forming a source/drain extension. In one embodiment, a method for forming an nMOS device includes forming a gate electrode and a gate spacer over a first portion of a semiconductor fin, removing a second portion of the semiconductor fin to expose a side wall and a bottom, forming a silicon arsenide (Si:As) layer on the side wall and the bottom, and forming a source/drain region on the Si:As layer. During the deposition of the Si:As layer and the formation of the source/drain region, the arsenic dopant diffuses from the Si:As layer into a third portion of the semiconductor fin located below the gate spacer, and the third portion becomes a doped source/drain extension region. By utilizing the Si:As layer, the doping of the source/drain extension region is controlled, leading to reduced contact resistance while reducing dopants diffusing into the channel region.

Embodiments of the present disclosure relate to methods for forming a source/drain extension. In one embodiment, a method for forming an nMOS device includes forming a gate electrode and a gate spacer over a first portion of a semiconductor fin, removing a second portion of the semiconductor fin to expose a side wall and a bottom, forming a silicon arsenide (Si:As) layer on the side wall and the bottom, and forming a source/drain region on the Si:As layer. During the deposition of the Si:As layer and the formation of the source/drain region, the arsenic dopant diffuses from the Si:As layer into a third portion of the semiconductor fin located below the gate spacer, and the third portion becomes a doped source/drain extension region. By utilizing the Si:As layer, the doping of the source/drain extension region is controlled, leading to reduced contact resistance while reducing dopants diffusing into the channel region.