Abstract: Methods and apparatus are provided for RF switches (100, 200). In a preferred embodiment, the apparatus comprises one or more multi-gate n-channel enhancement mode FET transistors (50, 112, 114). When used in pairs (112, 114) each has its source (74, 133) coupled to a first common RF I/O port (116) and drains coupled respectively to second and third RF I/O ports (118, 120), and gates (136, 138), coupled respectively to first and second control terminals (122, 124). The multi-gate regions (66, 68) of the FETs (50) are parallel coupled, spaced-apart and serially arranged between source (72) and drain (76). Lightly doped n-regions (Ldd, Lds) are provided serially arranged between the spaced-apart multi-gate regions (66, 68), the lightly doped n-regions (Ldd, Lds) being separated by more heavily doped n-regions (84).

Abstract: Methods and apparatus are provided for RF switches (504, 612) integrated in a monolithic RF transceiver IC (500) and switched gain amplifier (600). Multi-gate n-channel enhancement mode FETs (50, 112, 114, Q1-3, Q4-6) are used with single gate FETs (150), resistors (Rb, Rg, Re, R1-R17) and capacitors (C1-C3) formed by the same manufacturing process. The multiple gates (68) of the FETs (50, 112, 114, Q1-3, Q4-6) are parallel coupled, spaced-apart and serially arranged between source (72) and drain (76). When used in pairs (112, 114) to form a switch (504) for a transceiver (500) each FET has its source (74) coupled to an antenna RF I/O port (116, 501) and drains coupled respectively to second and third RF I/O ports (118, 120; 507, 521) leading to the receiver side (530) or transmitter side (532) of the transceiver (500). The gates (136, 138) are coupled to control ports (122, 124; 503, 505; 606, 608).

Abstract: A method of forming vertical trench inductor (10) includes providing a layer (11) and forming a plurality of trenches (12) vertically therein. The trenches (12) are filled with a conductive material (16) and etched using a photolithographically defined mask (17). The etching produces a conductive liner (18) covering two sidewalls (13) and a bottom surface (14) of the trench (12). A second conductive layer is formed and patterned to couple the conductive liner (18) covering a sidewall (13) of a first trench (12) to the conductive liner (18) of an opposite sidewall (13) of an adjacent trench (12) to form an inductive coil.

Abstract: A method of forming vertical trench inductor (10) includes providing a layer (11) and forming a plurality of trenches (12) vertically therein. The trenches (12) are filled with a conductive material (16) and etched using a photolithographically defined mask (17). The etching produces a conductive liner (18) covering two sidewalls (13) and a bottom surface (14) of the trench (12). A second conductive layer is formed and patterned to couple the conductive liner (18) covering a sidewall (13) of a first trench (12) to the conductive liner (18) of an opposite sidewall (13) of an adjacent trench (12) to form an inductive coil.