초록 ▼

Apparatus and method for increasing the time that a quartz crystal can sense the rate at which evaporated material is broadcast onto a substrate wherein a chopper employing a disk with a slot is disposed between the source of the evaporated material and the crystal to reduce the exposure of the crys

Apparatus and method for increasing the time that a quartz crystal can sense the rate at which evaporated material is broadcast onto a substrate wherein a chopper employing a disk with a slot is disposed between the source of the evaporated material and the crystal to reduce the exposure of the crystal to evaporated material to a fraction of the time that the substrate is exposed wherein the chopper frequency is not in tune with the dither frequency of the material evaporator. Barrier means prevents the chopper slot from significantly changing dimensions due to the build up of material on its defining edges, while shield means prevents the a crystal from being exposed to evaporated material from a source that it does not control.

대표청구항 ▼

In a control system utilizing a crystal for monitoring the rate of deposition of vaporized material from a material source, the improvements comprising: chopper means disposed between the source of vaporized material and the crystal, wherein said chopper means alternatively blocks vaporized material

In a control system utilizing a crystal for monitoring the rate of deposition of vaporized material from a material source, the improvements comprising: chopper means disposed between the source of vaporized material and the crystal, wherein said chopper means alternatively blocks vaporized material from reaching the crystal and permits vaporized material to reach the crystal at a frequency of at least once per second. A method for extending the operative time of an oscillating quartz crystal in a material deposition chamber where vaporized material is broadcast toward a substrate and the crystal the steps including: reducing the amount of material that is received by the crystal over time by alternatively blocking the crystal from and exposing the crystal to deposition material at a frequency of at least once per second.