Motorola Corporation

Devore Aviation

Other

Robert E Rutter

Stephen P Robb

Frank S d'Aragona

Robert Bruce Davies

Israel A Lesk

Lowell E Clark

Lewis E Terry

Robert M Jensen

Timothy Towne Hewit

A method useful in the backside processing of semiconductor wafers includes providing a semiconductor wafer having a first surface that has been substantially processed. The processed first surface of the semiconductor wafer is bonded to a handle wafer. Once bonded to the handle wafer, backside processing may be performed on the wafer. Following backside processing, the wafer is sawn while still bonded to the handle wafer. The individual dice are then removed from the handle wafer. This process involves fewer handling steps of the semiconductor wafer and the handle wafer provides support to the semiconductor wafer during backside processing thereby reducing opportunities for breakage.

Backside processing method

A portable flash tube intensity monitoring system which includes: an internal power supply; a human eye spectral response photodiode for producing analog signals, each of which is directly proportional to the intensity of each flash from the flash tube; electronics for converting each of the analog signals to a digital time function proportional to the intensity of the corresponding flash; electronics, including a microprocessor, for monitoring the digital time function, for flagging a time function which is below a preselected minimum, for communicating status signals to a localized operator display when the time function is below the preselected minimum, and for testing of an internal power source; a fixed distance indicator which allows accurate measurement from a remote coordinate location; and an operator display. The monitoring system is preferably integrally formed for ease of use and portability. The fixed distance indicator advances a predetermined coordinate distance to actively engage the system, and also allows for an accurate measurement of the flash tube intensity.

Portable light intensity monitoring systems

Flash tube and lamp monitoring systems. The flash tube intensity monitoring system includes: a human eye spectral response photodiode for producing analog signals, each of which is directly proportional to the intensity of each flash from the flash tube; electronics for converting each of the analog signals to a digital time function proportional to the intensity of the corresponding flash; and electronics, including a microprocessor, for monitoring each of the digital time functions, for flagging those time functions which are below a preselected minimum, and for sending a fault signal when a preselected number of consecutive time functions are below the pre-selected minimum. The monitoring system and flash tube are, preferably, incorporated into single unit for easy installation in the fuselage of an aircraft. The lamp monitoring system includes: a light pickup; a photodiode for producing an analog signal which is directly proportional to the intensity of the lamp being monitored; a line transceiver; an A/D converter; and a microcontroller. The microcontroller, which has a unique identification code, sends a command to the A/D converter only upon receipt of the matching poll command.

Automated lamp monitoring system for comparing light intensities with a

Briefly stated, the present invention provides a vertical current flow semiconductor device (17). The vertical current flow semiconductor device (17) includes a semiconductor substrate (12) having an intermediate conductor layer (16) on a surface of the substrate (12). An active layer (11) that is used for forming active elements (20, 21, 22, 23) of the vertical current flow semiconductor device (17) is on the intermediate conductor layer (16). The intermediate conductor layer (16) forms an ohmic contact with the active layer (11).

Vertical current flow semiconductor device utilizing wafer bonding

A protection circuit for providing short-circuit protection for a field effect transistor has been provided. The protection circuit senses when the voltage appearing at the gate and drain electrodes of the field effect transistor are both at a logic high voltage level, and responds to turn off the field effect transistor thereby preventing damage to the field effect transistor.

Short-circuit proof field effect transistor

An intermediate contact layer (16) is created within a vertical current flow semiconductor device such as an enhanced insulated gate bipolar transistor (EIGBT) (17). An active wafer (11) that is used for forming active elements of the device is wafer bonded to a conductor (16) that is on a surface of a substrate wafer (12). The wafer bonding not only forms the intermediate contact layer (16) but also diffuses a series of P (18) and N (19) regions into the active wafer (11) thereby forming ohmic contacts between the P (18) and N (19) regions and the intermediate contact layer (16). The substrate wafer (12) provides support for the active wafer (11) during subsequent wafer processing operations.

An insulated gate bipolar device is formed on a multiple conductivity substrate. The multiple conductivity substrate comprises interspersed regions of N+ and P+ semiconductor material. In a preferred embodiment, the N+ and P+ regions are arranged in a checkerboard, mosaic pattern on a bottom side of the substrate. The P+ region serves to conductivity modulate an N epitaxial layer in which the IGBT structure is formed while the N+ regions improve low current conductivity, reduce minority carrier recombination time, and make an integral drain source diode accessible from the drain and source electrodes.

Method of making enhanced insulated gate bipolar transistor

Power from an AC source is applied to a load under control of a power switching triac in response to signals from a feedback loop isolated from line voltage transients by means of a pair of opto-coupling devices respectively connecting the feedback loop to a load voltage sensor and the control electrode of the triac.

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Tempe, AZ, United States of America

Robert E Rutter