Abstract: According to a first aspect, the invention relates to a thermoelectric module (10) that comprises a thermoelectric layer (15) comprising one p-type (7p) and one n-type (7n) portions presenting together an upper and a lower main surfaces (11,12). The thermoelectric module (10) further comprises a first and a second thermal resistor elements (1r, 2r), and a first thermal bridge element (3c), between and adjacent to the first and second thermal resistor elements (1r, 2r). The first and second thermal resistor elements (1r, 2r) and the first thermal bridge element (3c) cover the whole lower main surface (12). The p-type (7p) and the n-type (7n) portions are adjacent and directly coupled by an interface (7i). The first thermal bridge element (3c) spans at least over the orthogonal projection of the interface (7i) on the lower main surface (12).

Abstract: The method of the invention relates to a method for welding a first (20) and a second (30) layers together. The second melting temperature of the second layer (30), Tm,2, is lower than the first melting temperature of the first layer (20), Tm,1. After having formed a layup (50) by placing the first layer (20) on top of the second layer (30), a rotating tool (70) is pressed and translated over at least a friction portion (15) of the upper surface (20u) of the first layer (20) such that the temperature reached by at least a portion of the upper surface (30u) of the second layer (30) is higher than the second melting temperature, Tm,2. Restraining means allow preventing molten second material from flowing out of the layup (50). Materials of first (20) and second (30) layers are chosen among the following materials: metals, semi-metals, or semiconductors.