Abstract: A method of forming a ball weld during the fabrication of a semiconductor device wherein a pad (3) and a gold ball (9) to be bonded to the pad is provided over the pad. Ultrasonic energy from an ultrasonic energy source (11) is applied to the ball to soften the ball while concurrently applying a compressive force to the ball to force the ball against the pad. Reflections of the ultrasonic energy are monitored to provides an indication of completion of the bond of the ball to the pad from the application of energy and compressive force to the ball. The application of energy to the ball is terminated responsive to detecting a parameter which provides an indication of completion of the bond. A preferred embodiment of the step of detecting includes providing a piezoelectric device (13) providing a current output responsive to the reflections of said ultrasonic energy and providing a monitor (21) to detect from the current output the indication of completion of the bond.

Abstract: A system for the prevention of theft of a motor vehicle comprising a valve system and electronic package for the control thereof. The valve system is connected between the master cylinder and the slave cylinder of the vehicle brake system and is selectively actuatable to cause the brakes of the vehicle to lock when the vehicle's ignition is turned off. The electronic package is connected to the valve system and the ignition system for generating an alarm system for generating an alarm system for selectively actuating the valve system. A keyboard is connected to the electronic package for controlling the operation thereof and means are provided for receiving a multi-digit code in the keyboard to effect actuation and deactuation of the valve system and the release of the vehicle brakes for operation of the vehicle. A series of separate alarm sensors are provided in conjunction with the electronic package for affording added safety and theft deterrence.