Sensor head for crystal oscillator type of film thickness monitor

Patent metadata

Field	Value
Publication number	US-10767987-B2
Application number	US-201816469210-A
Country	US
Kind code	B2
Filing date	Mar 6, 2018
Priority date	Jun 28, 2017
Publication date	Sep 8, 2020
Grant date	Sep 8, 2020

Abstract

A sensor head has: a sensor head main body which has disposed therein the stepping motor; a holder which has disposed on an upper surface thereof a plurality of crystal oscillators and which is driven for rotation by the stepping motor; and a mask body which is mounted on the sensor head main body so as to cover an upper surface of the holder and which has opened therein a film-forming window faced by one of the crystal oscillators. The sensor head also has: a first electrode fixed to that portion of the sensor head main body which is located right under the film-forming window; and second electrodes which are in electrical conduction with each of the crystal oscillators and which are disposed to protrude under a lower surface of the holder.

First claim

The invention claimed is:

1. A sensor head for a crystal oscillator type of film thickness monitor, including:
a sensor head main body having disposed therein a stepping motor;
a holder having disposed therein a plurality of crystal oscillators in a same circumference at a distance from one another, the holder being adapted to be driven for rotation by the stepping motor;
provided that a direction from the sensor head main body toward the holder is defined as an upper side, a mask body mounted on the sensor head main body in a manner to cover an upper surface of the holder on which is disposed each of the crystal oscillators, the mask body also having opened therein a film-forming window facing any one of the crystal oscillators, the sensor head further comprising:
a first electrode which is provided onto a plate part that is fixed at one end thereof to a supporting base and that is elongated in a tangential direction of the holder, which is fixed to that portion of the sensor head main body which is positioned directly under the film-forming window; and second electrodes respectively in electrical conduction with each of the crystal oscillators, the second electrodes being disposed to protrude out of a lower surface of the holder such that, when the holder is rotated by the stepping motor to a phase in which any one of the crystal oscillators and the film-forming window coincide with each other in a vertical direction, the first electrode and the second electrodes, both being made of same kind of metal, come into contact with each other for electrical conduction,

wherein a sliding plate part is provided onto the plate part and is disposed for supplying, before the first electrode comes into contact with one of the second electrodes, a surface of the second electrodes with a solid lubricant by sliding the second electrodes with urging force of the plate part.

2. The sensor head for a crystal oscillator type of film thickness monitor according to claim 1 ,
wherein the sliding plate part has a sliding surface along which the second electrodes slide accompanied by the rotation of the holder,
wherein the sliding surface has a Vickers hardness which is lower than that of the second electrodes, and has a central flat part and inclined surface parts which are respectively formed in continuation with opposite sides of the flat part.

3. The sensor head for a crystal oscillator type film thickness monitor according to claim 2 , wherein the sliding surface of the member is constituted by fluororesin or graphite.

4. A sensor head for a crystal oscillator type of film thickness monitor, including:
a sensor head main body with a stepping motor SM or a pneumatic rotary actuator being disposed therein;
a holder having disposed therein a plurality of crystal oscillators in a same circumference at a distance from one another, the holder being adapted to be driven for rotation by the stepping motor SM or the pneumatic rotary actuator;
provided that a direction from the sensor head main body toward the holder is defined as an upper side, a mask body mounted on the sensor head main body in a manner to cover an upper surface of the holder on which is disposed each of the crystal oscillators, the mask body also having opened therein a film-forming window to which faces any one of the crystal oscillators, the sensor head further comprising:
a first electrode fixed to that portion of the sensor head main body which is positioned directly under the film-forming window; and
a second electrode which is in electrical conduction with the respective crystal oscillators and which is disposed to protrude out of a lower surface of the holder such that, when the holder is rotated to a phase in which one crystal oscillator and the film-forming window coincide with each other in a vertical direction, the second electrode comes into contact with the first electrode so as to be in electrical conduction,
wherein an insulating body is disposed on both sides, as seen in the direction of rotation of the holder, of one of the first electrode and the second electrode, the insulating body coming into sliding contact with the other of the first electrode and the second electrode, and
wherein a flat part is formed at a top of the first electrode and defines an upper surface of the flat part,
a hole is formed at the flat part,
a contact member is formed in the hole, and
an upper surface of the contact member is positioned so that a distance between the upper surface of the contact member and the lower surface of the holder is larger than a distance between the upper surface of the flat part and the lower surface of the holder.

5. A sensor head for a crystal oscillator type of film thickness monitor, including:
a sensor head main body having disposed therein a stepping motor;
a holder having disposed therein a plurality of crystal oscillators in a same circumference at a distance from one another, the holder being adapted to be driven for rotation by the stepping motor;
provided that a direction from the sensor head main body toward the holder is defined as an upper side, a mask body mounted on the sensor head main body in a manner to cover an upper surface of the holder on which is disposed each of the crystal oscillators, the mask body also having opened therein a film-forming window facing any one of the crystal oscillators, the sensor head further comprising:
a first electrode fixed to that portion of the sensor head main body which is positioned directly under the film-forming window; and second electrodes respectively in electrical conduction with each of the crystal oscillators, the second electrodes being disposed to protrude out of a lower surface of the holder such that, when the holder is rotated by the stepping motor to a phase in which any one of the crystal oscillators and the film-forming window coincide with each other in a vertical direction, the first electrode and the second electrodes, both being made of same kind of metal, come into contact with each other for electrical conduction,

wherein
the holder further has a ring plate part with a lower surface thereof,
a plurality of radially elongated slit-shaped recessed parts is formed in the lower surface of the ring plate part, and
a lower end of each of the second electrodes is made to protrude downward into the recessed part.

Assignees

• Ulvac Inc

Inventors

• OGUMA Yousuke
• Maeda Akihiro
• Kaida Yuki
• Kotaka Manabu
• OKAMURA Kou

Classifications

• G01B17/025 Primary

  for measuring thickness of coating · CPC title

• C23C14/52 Primary

  Means for observation of the coating process · CPC title

• G01B17/02 Primary

  for measuring thickness · CPC title