Abstract: A mercury cadmium telluride (MCT) substrate 30 is immersed in a liquid 34 (e.g. 0.1 molar concentration hydrochloric acid) and illuminated with collimated radiation 24 (e.g. collimated visible/ultraviolet radiation) produced by a radiation source 20 (e.g. a 150 Watt mercury xenon arc lamp). A window 26 which is substantially transparent to the collimated radiation 24 allows the radiated energy to reach the MCT substrate 30. An etch mask 32 may be positioned between the radiation source 20 and the substrate 30. The MCT substrate 30 and liquid 34 may be maintained at a nominal temperature (e.g. 25.degree. C.). Without illumination, the MCT is not appreciably etched by the liquid. Upon illumination the etch rate is substantially increased. A further aspect is the addition of a passivant (e.g. iodine) to the liquid which forms a substantially insoluble passivation layer 36 on the substrate which is removed or partially removed by the radiation 24.
Abstract: A molecular beam epitaxy (MBE) system (10) is provided to grow thin film, epitaxy layers (44, 46, 48, 50) on compound semiconductor substrates (40). A mass spectrometer detector (95) is used to monitor and control the flux from selected sources (21, 23, 25, 27) within the MBE system (10). A uniform layer of indium gallium arsenide (46, 50) may be grown on a semiconductor substrate (40) by controlling the indium flux with respect to substrate (40) temperature and time. An epitaxy layer (46) of indium gallium arsenide with uniform mole fraction concentration and reduced lattice strain is produced.
Abstract: A MOSFET (100) device having a silicon carbide substrate (102) of a first conductivity type. A first epitaxial layer (104) of said first conductivity type and a second epitaxial layer (106) of a second conductivity type are located on a top side of the substrate (102). An insulator layer (108) separates gate electrode (112) from second epitaxial layer (106). A drift region (118) of the first conductivity type is located within the second epitaxial layer (106) on the first side of the gate electrode (112). The drift region has an extension which extends through the second epitaxial layer (106) to the first epitaxial layer (104). Source regions (116) and body contact regions (122) are located within the second epitaxial layer (106) on the second side of the gate electrode (112). Source regions (116,) and body contact regions (122) are of opposite conductivity type. Source electrode (126) electrically connects source regions (116) and body contact regions (122 ).
Abstract: This is a package [10] for an rf device [11] operable with a characteristic impedance providing a plurality of terminals [12-19] and [101] for effecting circuit connections to the device, the connection between at least one of the terminals and the device being matched in relation to the characteristic impedance. Other devices and methods are also disclosed.
Type:
Grant
Filed:
May 21, 1993
Date of Patent:
December 27, 1994
Assignee:
Texas Instruments Incorporated
Inventors:
Stephen R. Nelson, Buford H. Carter, Jr., Tammy J. Lahutsky, Glen R. Haas, Dennis D. Davis, Charles W. Suckling, Glenn Collinson